Positive test, then 2 negatives, then bleeding for 4 days, then positive??

Simplemama

Guys, I have no clue what is going on. I took two tests after being 3 days late and they were positive. I started bleeding that day and had (what I thought) a full period with cramping and all. I did take tests in between and they were negative. Well, my bleeding has now stopped and i have been having sore nipples, a full feeling and nausea so I took a test last night and it was a faint positive. (It is fainter than the very first one I took, but definitely there.) Has anyone else experienced anything similar?