HELP PLEASE!

I'm 20 years old and was put on an anabiotic for a bladder infection! The anabiotic was for 2 weeks! I didn't skip a pill. During that time my boyfriend and I had sex. I'm on birth control pill but anabiotics cancel them out. He finished inside me twice and I still Took my birth control everyday. It's been 17 days since I finished my anabiotic and for all 17 days I've been on my period. Heavy bleeding and cramps that won't stop. I still have been taking my birth control but it still won't stop. Could this mean I'm pregnant??