On birth control, no period.?

Okay this is my third month on this birth control. I forgot to take it two days in a row, and my boyfriend and I had sex and he nutted in me. I had gotten my period the 3rd day I didn't take my birth control. Then I took all 3 days, and am going on with it, and am still supposed to have my period. But I have no period. Just a little itty bitty brown tint to a tampon. (TMI) but sorry. I just need to know if you guys think its worth buying a test or waiting another month ?