Pregnant or Not Pregnant?

I had posted in another group which may have been insensitive and was advised to move my post here. So my boyfriend and I had unprotected sex on 7/22/19. My fertile window was estimated for 7/16-7/22. My period is 2 days late as of today and I’ve taken a few pregnancy tests that indicated negative until today. I also experienced some light but dark spotting throughout the day and just took 2 tests this evening that indicated positive. I initially assumed it could be a false positive but was told that’s uncommon. I’m just dumbfounded how I could have negative tests yesterday and positive tests today. So am I pregnant or could these be false positive?