Missed period positive then negative

I was supposed to get my period Monday and I never got it. I have taken many tests and up until yesterday they were all positive. Well I woke up this morning to take another (very paranoid) and it was negative. I’ve taken 2 others also today, all of them negative. I’m extremely confused to what’s happening. Does anyone have any idea of what could be happening? I’m on vacation so can’t see a doctor until next week.