Brown Discharge two weeks before period?

[XbellaX01]

So, I'm 17 years old. I've been on the pill for almost three years now. I've had to contemplate going up in dosage due to easily spotting if I take a pill three hours late. But the point is, I spot easily. Or, I used to. For three months, I haven't spotted I believe. I take my pill at 8 pm every night and sometimes a little bit after or before. My boyfriend and I had sex twice in March, both times he didn't ejaculate inside of me. We're very careful. Two weeks later, I got my period but it was weird. It was brown discharge two days before and then I got a light period for the next three days. I was worried for a moment but I felt fine. I haven't had sex since but I messed up on my pills. I was late by two hours on the past two or three due to activities. Now, I'm two weeks from my period due date and I'm having brown discharge (yesterday I had normal colored spotting so bright red) and I'm having cramping in my lower back. Is it just from my pills? I'm worried. Any advice is helpful. Thank you :)