Help!

Martha
So I took a pregnancy test last night and when I checked it this morning it had two lines and I took another and again positive, I went to the store to buy a third test and that one was negative, I went to the doctor for a pap smear and had a pregnancy test a day it came back negative.. Doctor said I might have started my period cause I bled a Lil while she was doing the pap smear..  Has anybody been through this?? Could I still be pregnant?? I been having cramps, sore breast, heartburn!! I am a day late on my period.