[Age of Ignorance]

Okay, so my girlfriend has lately been having some issues with sharp pains in her lower abdomen (about an inch or two below the middle of her waistline, directly in the center, below her bellybutton). These pains get so bad that she feels like she's going to vomit. She says they're not like what you get from muscle tightness or cramps. She says they're a sharp pain, localised to the one spot.

We've been having sex for close to 3 months now (Christmas day, believe it or not). She was a virgin. I was not. I've had 1 long-term sexual partner and 2 sexual encounters prior to her. She'd never done anything sexual. She says that the pain is at its worse immediately after sex, and slowly goes away over the course of 2 hours. However, she gets these pains sometimes when we're not having sex (the first time she felt the pain today was at midday, and we didn't have sex until 9pm, and haven't had sex for a few days prior to today).

She started on the pill 2 weeks ago (Levlin). We continue to use condoms and have used condoms since we started having sex. We're definitely protection-happy. We use condoms (they're called Skyn, extra-lubricated, made by Durex, I think.), I pull out prior to orgasm, and she's now on the pill. She finished her period last week. So, let's rule out pregnancy, for a start. I highly doubt it could be that, considering she's had the pains off and on since (she says) we started having sex, and she's had 3 periods since then.

I've also thought that she could be allergic to latex condoms or the lubricant in the brand we use. However, since it occurs when we don't have sex as well as after/during sex, I doubt it would be that.

I've also considered that perhaps I bruise her cervix during sex. I'm not that big, though (I'm roughly just above average, though she seems to think I'm big). I'm also quite gentle, though at times I do tend to be quite deep (I'm sorry if that's too much information). When I suggested it to her, she told me it "could be that", but she doesn't think so because if it were, she'd feel aches, not sharp stabbing pains.

I also thought that maybe it was her appendix, since she hasn't had it removed, but the pain is localised to the center, not to the right, as where the appendix is.

So as far as peace of mind goes, can someone tell me it's not me doing this to her? Can someone also confirm that it's highly unlikely she's pregnant (I'm a bit of an obsessive type over this)? What else can cause this sort of symptom?