I'm a 23 year old guy who's just become sexually active for the first time. To put it bluntly, I'm having trouble staying hard. The first time I had sex, I didn't feel like I was very hard, but my girlfriend was on top so it ultimately worked. This last time, I tried to be on top, but I couldn't stay hard for more than a few seconds and went soft as I tried to put it in. After a lot of foreplay, we were finally able to have sex...though like last time, she had to be on top and I didn't feel like I was hard enough and felt like I would lose it at any moment. Whenever we kiss, etc. I am hard, but when I know more is going to happen, I go soft and have to work back up again. I'm attracted to my girlfriend, I'm a young, healthy guy, and I was masturbating regularly before I started dating this girl so I know its not a physical problem. She is really cool about it, but for both of our sakes I want to get this taken care of. At first, I thought it might be performance anxiety, but this second time I assumed it would be better, but its not. Any advice/insight?