I fucked up with my brother

Ok, so, this one is a bit special. To be honest, I really wasn't sure I wanted to share it here and I don't really know what to think about my current situation. I'm aware that what will come next seems very unusual, but something a bit stupid happened with my brother and our relationship took a bit of a weird turn, and I'm asking myself a lot of questions.

Anyway, my brother and I have been living together for 3 years. He's 2 years older than me (he's 25) and as I got along well with him, we naturally took an apartment together for our studies.

Everything has always been very normal between us. I had a boyfriend for a very long time and he had a girlfriend during 3 years. They broke up two years ago and he has brought home a few girls since. We had a completely normal sibling relationship, its arguments, and its moments of brother and sister complicity, and nothing more. But since breaking up with my ex, our relationship has changed. I have the feeling that the breakup made me open my eyes to the complicity that I had lost with him and that we both wanted to find it again. I realize that we are closer and closer, we look at each other differently, we share more discussions, we are much more tactile towards each other. We even started talking about sex together.

Anyway, this may sound stupid, but a few days ago, we got carried away into something completely stupid. We were both at the apartment spending the evening together drinking wine and we started talking about sex. I was super euphoric and he was too, we laughed a lot, we talked about our experiences, about what we liked, both going into very intimate details. We were both slightly tipsy, and I must admit, our discussions had made me a little excited. I don't remember exactly how we ended up in this situation but at one point, I was telling him how much I loved to suck dicks, bragging about how good I was doing it and that no guys has ever lasted more than 5 minutes in my mouth. He smiled and replied in a provocative way, that I only come across premature ejaculator. I told him that if he wasn't my brother I would have shown him that he wouldn't last 5 minutes in my mouth, to which he provocatively replied that if I wasn't his sister he would have accepted the challenge to prove me wrong. It somehow triggerd me, and in the heat of the moment I told him "haha you are so cocky, maybe i should blow you to prove you wrong", which he instantly replied "and maybe I should let you do it to see you fail" winking at me. We started to tease each other, provoke each other. I knelt in front of him to provoke him. I dare you to, I'm sure you'll chicken out, etc etc.

I just went with the flow. Slowly, I slid his pants down to reveal his penis, which I grabbed with my right hand before plunging it into my mouth. I started sucking him slowly, but with a lot of pressure and saliva, sliding my tongue along his cock. At first I sucked him out of provocation, but as I was feeling his cock growing in my mouth, and feeling him reacting to the comings and goings of my mouth along his shaft, I began to get very horny and I was blowing him like he was one of the guy I would fuck. Everything happened as if it were natural. It was surprising and so incomprehensible

As I was sucking him, several times I wanted to stop, and I had the feeling that he was hesitating too, but each time, the excitement and pleasure it gave me was stronger and I kept going. It was insane, I was blowing my big brother and I was loving every part of it. I wasn't expecting that from myself. It had been 2 minutes since I started, and I started to feel like he wasn't going to last very long. Part of me knew I had to stop but another part of me was dying to feel him cum in my mouth. I looked into his eyes and saw that he couldn't take it anymore.

And then we stopped and burst out laughing. I don't know which one of us stopped. I think it kind of happened naturally before it would be too late. We calmed down, we continued to laugh, we were a little embarrassed, but still a little tipsy from alcohol. We talked for another ten minutes, then we each went back to our room.

It was only the day after, that we understood that something radical had happened. For my part, I had mixed feelings about what had happened. On one hand I had enjoyed this moment and the excitement I had felt doing it, but on the other hand it was a bit strange and I didn't want any awkwardness between my brother and I. When I came back home in the evening after school, I smiled at him and asked if he was okay. He told me he was, but I had the feeling he was uncomfortable. I asked him how he was feeling about what happened the night before, and he said he wasn't sure, it was weird, and maybe it wasn't a good idea to do this between brother and sister. I told him I agreed and as he seemed worried, I reassured him that what had happened was not serious and that it would be our little secret. He smiled and seemed reassured. I told him that in any case, I had enjoyed this evening with him and that even if it was weird, I had loved having fun with him. In response, he stammered something like "uh, yes me too, but uh, it's still a bit weird, right? What if uh, we hadn't stopped ? what would have happened ?". I looked him in the eyes with a mischievous look and told him "I have a little idea, but since we stopped, you'll never know" I smiled at him and went back to my room.

I thought, by de-tramatizing what had happened, that there was no longer any awkwardness between us, but the next day, he seemed distant and cold. The few words we had in the morning were weird and he left for a 4 day weekend in the early afternoon without saying goodbye. I texted him to see if he was okay but he didn't text me back. Now I'm a little worried and I don't really know what to think about what just happened, and if it's serious.