Confused about being pregnant !

hey girls, I was supposed to get my period on the 30th, I didn’t get it so I took a test the day it was expected, it said positive.

I took another test and another test and another test😂 I went a little crazy on taking tests to be certain! I went through about ten tests, all positive. Then I started bleeding pink blood and I got really bad cramps in my stomach and bad back pain, the blood started getting heavier, now tests say negative? is it because of the blood getting in the way or am I not pregnant