I'm a 17 year old male and have been with my girlfriend for only about a month now. We've tried to have sex twice and I'm having a bit of an embarrassing problem. We'll get naked and start getting down, but whenever it's actually time for me to go in I lose my stiffy. She's mentioned that I seem really shakey during this as well. I'm a technical virgin and my only sexual experiences have mainly been while really drunk or high at various parties. She's had a fair bit of sex but doesn't really seem all too empathetic as she hasn't ever had to deal with this problem before. I want to be able to please her and have sex but I have no idea how to get over this. Thankfully she's trying to be understanding and we're still together. I just don't want to keep making her take all of her clothes off, getting her horny, and then not being able to perform. I think I'm just incredibly worried about my performance and what she'll think. I don't want to have to buy viagra off the street, so does anyone have any experience or advice to get over this "stage-fright"? 
