Period while on the pill

Hey ladies, I’ve been on the birth control pill for a little over 2 months now. I’ve been having mild cramping for the past 2 days and dark spotting today but it’s not time for my period yet. I’ve been on a different kind of pill awhile back and I’ve never had this before. Has this happened to anyone else? Is it normal? Also my boyfriend and I occasionally have sex without condoms but he always always pulls out. Could it possibly be implantation bleeding? What should I do?