Is it my birth control or am I pregnant

A couple of weeks ago I had sex with out a condom. The day after I started taking my birth control again. A few days later I started getting spotting. After a week the spitting. Stopped for a few days and it started again today. I've also been having some stomach pain. When I started the pill It was about a week after my period ended. I'm wondering if my birth control is just messing with me or could I be pregnant