How am i pregnant after taking the morning aftet pill within 8 hrs of ?

I had & the condom broke so I got the morning after pill and took it within 8 hrs of having . My period was supposed to come on the following week, meaning my time of ovulation had come and gone. That was the first time I had had in about 5 months so i know it wasnt bc of me previously having . I also read that taking diuretics can cause a false positive, although rare. I'm taking one to lose weight but 3 of 4 tests said positive. IDK what to do?