Weird period or pregnant.

I've been on bc pills since February and I've had normal periods every month ever since, 5ish days with cramps and bleeding. Well this month idk if it was a period or not. I was suppose to get it on the 3rd of october. And it wasn't normal lasted less than 2 days and mucusy and only tinged pink. Not a red like normal. I've take 3 hpt all negative but I've read online and heard from many people that with the circumstances I could be pregnant. Anyone else go through this and was pregnant or what should I do??