Period-like spotting while on the pill?

Betty

hi, I take the Sprintec combination pill. it is supposed to be a low dose pill. On Saturday the 24th of March I accidently took two pills, then on Friday the 30th of March I took my pill 17 hours late. the next day I started spotting and having light pink or even brown discharge, no blood. then the next day there was a little bit and now I'm regularly wiping and seeing either red or brown blood. its showing up un my undies too. i dont have any panty liners, so I've just been using pads and its not enough to where it soaks through the pad but it is usually bright red and way more than just a few drops. This is the 12th day of this occuring with no end in sight. I started the pill mid-cycle on February 25th, just a few months ago. I'm nervous I could be pregnant as there was a day where I had a sexual encounter after about week 3 day 1 or 2 of being on the pill and on week 2 days 1 and 2 I took the pill 9 hours and 7 hours late respectively. I'm unsure of if semen entered me or not(check my other posts) and cannot shake this fear. any advice or answer is appreciated. Prom is coming up in a little more than a week and I dont want to be bleeding then. thanks!