i have been on the birth control pill for about 5 months now, and at the end of this month i didn't get my period when i was supposed too ( when i'm on the grey color pills). now i am a week late with my period and today i got some spotting that was light red and a slight brown color. me and my boyfriend never really use a condom other then a couple times this month. is there a chance that i could be pregnant or is this my period?