I've been having bad back pains, knee pains and stomach pains for about a month or two now. It can't be pregnancy because I have had a regular period the past few months and have taken pregnancy tests that say negative; so that can't be an option. Sometimes I have pain during intercourse when penetration is deep. I haven't thrown up or anything, and I feel bloated constantly, I frequently get headaches about a 8 on a scale of 1 to 10. My abdomen hurts almost every morning or if I'm laying on my back for long periods of time. I haven't went and seen a doctor, I just would like to have some clue as to what's wrong with my body.