I Had My Mirena Removed 21 Days Ago And When

i had my mirena removed 21 days ago and when i got it taken out the doctor said that i should go back to my regular period (which i have no clue when that is because i had the mirena in for 3 years). The doctor had me start the pill the day after I got the mirena removed and i know that normally when your on the pill the last row of pills is when you should start your period. I'm just curious whether I should start my regular period back within the next couple of days since i take the first pill on the last row tomorrow or if its going to be all out of wack due to having the mirena for a while..?