Help! So confused/worried

Me and my boyfriend had sex and I just got off of birth control like a week ago and i started my period well I think it was my period but it was supposed to start on the 8th of this month but instead started on the 9th but my bleeding was very light and I usually last 5-6 days but this time I only lasted 2. The third day was mainly light blood but with brown discharge. We had sex again unprotected last night and I started bleeding again (it was light red/pink) I have no clue what this means.