Curious about whats going on with my "flow" ?

I was on birthcontrol for 4 months, I stopped taking them bc I got migranes. For four days, I barely bled, I'm not sure if its a period.. Cuz I only bled once each day for about 20 minutes each. For the first 3 days it was light pink ( very light ) and the forth day was a little more brownish/pink. ( Verrrryy light) was it my period.. And the birth control is just messing it up ? I know the chances of being pregnant are there, especially concidering I had a 6 month old baby, but it cud also be from not taking the pills ?