Late period

I recently started birth control cause I thought me and this guy were getting serious. Anyways. I started it a week after my period ended rather than the following Sunday bc my dr appointment wasn’t until I was already off of it. She informed me it wouldn’t be effective til a few weeks after my next period . Well around when my period was suppose to come I kept spotting dark brown blood and it was like funky blood not normal what’s so ever. I had unprotected sex the week after my “period” and nowwww this month I have not received my period lol. Could I be pregnant ? I know I added a lot of nonsense but idk how to feel I just hope I’m not I’m a week late and I’m worried