Pain during doggy style only?

I have been sexually active with my boyfriend for two and a half years now, and up until September 2011 when I got a colposcopy done, sex never used to hurt (with the exception of soreness if we had done it more than a few times). However, since then, I occasionally felt pain in my abdomen while we're doing it, especially in the doggy style position. And when I went to the bathroom after, I sometimes noticed a little bit of blood. I suspected this was due to the colposcopy, and when I told a doctor about it, she agreed and said this would likely pass with my next period. It didn't. Nor after the next one, or the next one. Due to occasional long distance, we have taken long breaks from having sex - which I thought would give my cervix time to heal - but even this has not helped. It's been almost 9 months now and I still feel pain whenever he enters/thrusts from behind, and I even occasionally bleed. I have gone to the doctor on multiple occasions to ask what's wrong, and I've received no definitive answer.

If I'm not sore already, I only get abdominal pains during the doggy style position. Yes, my boyfriend is well-endowed, but it's never caused me pain before. I know that it might just be his penis hitting my cervix, but that was never an issue before, and shouldn't all of the long gaps between having sex have allowed my cervix to heal from the colposcopy (the doctor who did the procedure said it would only take a week)? I do plan on seeing a doctor, but I'm frustrated with the amount of doctors who have told me that nothing is wrong and that I just need to lubricate (which I do!). Has anyone else had this issue and consulted a doctor who knew exactly what it was?? I would greatly appreciate any feedback. Thanks.

[RainLover71]

maybe try another position and ask him to go slow so you feel comfortable.