Hello. Since puberty my periods have been pretty irregular. But, For the last 11 months it was coming every month. I haven t had a period since may and I feel pretty pregnant. I have headaches , strong cramps that come and go, and I feel bloated. I took six pregnancy tests and the fourth one came back Positive. The other ones came back negative. I don t know what to do. Could I still be pregnant? I wonder if my body doesn t produce enough hcg . When my sister got pregnant, all the tests (urine and blood) came back negative and she could only detect the pregnancy when she was 6 1/2 months pregnant.