Brown discharge/could i be pregnant?

Ive been on birth control for a year now but recently switched to new pills. This is my second month on them, i shouldnt get my period till 2 weeks from now. But ive been having brown discharge for about a week now. My partner and i dont use protection but he does pull out atleast. Im young and i dont want a baby right now so if anyone could give me some peace of mind it would be appreciated.