Please help

Tara • Confident and crazy and two words that start with C....
I've been spotting a lot and I don't know why it's not painful but I've been getting it for like a month I got it a week before my period then I had a lighter period and now it's happening again and I'm on birth control and I'm really scared because I looked up stuff and it said chlamydia but I don't believe it's that serious but I'm scared so please help