8 days overdue, 1 test positive, the other negative.

Hi ladies,
I'm now 8 days overdue. I took a test 2 days ago that seemed positive. After that, I took 5 more tests and they were all negative. This morning I really had a pinkish tint on my toilet paper, so I expected my period. However, the next time I was on the toilet, there was nothing left on the paper.
I find all this so strange. I'll add a photo of that positive test. Because the tests after, and even until last night, were negative, I had started to believe I wasn't pregnant.
What do you think?