Incomplete.

I've been trying to conceive for 2 years now with no luck at all. I think there may be something wrong with me. My doctors say there isn't. I have issues with my stomach they say it's irritable bowel syndrome but I have a friend with very similar symptoms to me and she has stage 4 endometriosis. I'm so worried. 8 years ago I had to have a termination at 8 weeks pregnant as my baby wasn't developing properly and my body would have rejected it anyway. That was the hardest decision I ever had to make. Since then I've longed for a baby and it's never happened. I don't know. Maybe I'm being punished?? I feel so incomplete and very depressed. Xx