Hey all ! Well i'm 17 years old virgin. So like 2 days ago, me and my girlfriend were at a friend's party. I used some alcohol, and so did she. So we went to another room, and started to make love, I gave her foreplay, I went down on her, and according to her nailprints on my back, she liked it. But when I was about to penetrate her, I just lost my errection. I put on the condom, and when I was about to enter, it just went limp, nothing, just went soft, and I was not able to get it hard anymore. But when we just meet eachother daily, and do some kissing, and just play with each other, my penus is rock hard,and when I masturbate, it is rock hard, really HARD ! But after that night, I'm really worried about it. OMG I feel like I'm like only a half-man, or something. She is also a virgin, and it was the 1st time for both of us, and I just destroyed it, I feel so misserable, depressed and so ashamed. She said to me it's ok, and she understands it, but im not sure, if she really thinks like that. Please guys give me some tips, I soon got exams comming, and due to this problem, I'm really depressed. Was it becouse of the alcohol, or what ? Please Help

And like one of the topics below, I feel so low, and lonely, I also want to run far away, so noone knowes me I exist. I dont want to speak to my friends about this or anything. I feel so lost.
Please help.