Has anybody experienced this?

I’ve been on tri lo sprintec (combo pill) for almost a year and no issues with it. Well last month on my period it became super light and barely there it use to be like a crime scene and this month it came late by a day or two and not enough blood for a tampon I am also cramping. I was scared I was pregnant I had unprotected arc on may 26th and he pulled out. I took a pregnancy test two days ago it was negative and I took another this morning snd it was negative is there still a chance of pregnancy? I also feel the bc is taking my period away has anybody experienced that does it mean I need a higher dose of birth control?