Spotted for a day... what is going on?

Li

I had my period twice in April that’s when I started birth control. I stopped taking if after a month. i got it twice in May also. It says my period is due in 4 days, I went to the bathroom a wiped yesterday and it was light blood and then that was all... idk what’s going on. I’ve had a period since unprotected sex I’m pretty sure.