I [20, F] am diagnosed with borderline disorder and panic disorder. My BPD is like feeling nothing at all or feeling everything at once.
So, whole my life I've been asexual, I didn't have sex and things like that. Yesterday night (well it's today morning) I got drunk asf (which was my first decision based on my sudden impulse of 'Ayyy, I am so full of emotions! I am not bored by this idea after like 6 months of being bored!') and out of nothing I got "horny", which my male friend I was with got too. Horrible thing, we actually went and "did it", sort of, just with hands, then many touching and kissing. In the middle of the whole thing I've suddenly 'snapped back', I was sober out of nothing. And I was like "WHAT THE FUCK DUDE?!"
And now, when I am back at my 'normal' - meaning I am not very affectionate - I am dead inside. I am so horribly embarrassed, I am so ashamed. This was not me, this was some sudden 'euphoria' mixed with alcohol. 
To make it clear - I don't shame anyone for having sex and things, no, I kind of envy you you can, because I am so sex repulsed normally. 
Well I waited til the morning, I am sick, I almost have fever from this intense situation and when I came home I haven't stopped crying since. I am 20, guys, freaking 20 years old. And right now it's even harder for me because I cannot explain to my mother what happened. I am ashamed beyond possible. I seriously want to die.
I cannot get it out of my head, the images are sticked there and I am panicking because I want them out, I don't want them. I've seriously hit myself in the head like half hour ago, now I have a bruise. I didn't even planned to hurt myself, I was walking around the house and I've just hit myself repeatedly. What the heck, guys. 
Oh my god, it even seems like I can smell the same smells there were.
I am going crazy! I feel like jumping out of the window.