If a woman doesn't come or have an orgasm, can her ovaries hurt just like a man's testicles can hurt if he doesn't come?

I am a twenty-one-year-old virgin who has just recently started seeing a girl very seriously. I am frustrated at how my body reacts to the slightest physical stimulus. Holding hands, talking about physical affection, even thinking about kissing gives me an erection. I am not thinking about sex, and we are not going to have sex until we are married, but I can't believe how frequent these erections are. I know it's common for guys my age to have erections, but just being with a girl I care about gives me one, and it's not easy to hide, and I don't want her to think the wrong thing. I used to masturbate and view pornography a lot but I finally stopped because I didn't agree with it. I stopped about the same time I met her. Do you think that my past is causing my body to want something I'm not going to give it?

1) It seems that I can't maintain an erection for more than a couple of minutes during intercourse. In fact, sometimes it doesn't seem to want to get up and play at all. The girlfriend is really starting to take this personally, but I know it's not her fault. Help! Are there any vitamins, diets, etc. that may help?

2) To put it very simply, I am having trouble having erections for a while now. I used to be able to. I can't have them at all, during intimate encounters or during masturbation. I get a little "hard" but cannot get completely hard. Could you please help me? Thank you!!