Early Period help

erial
I am on the pill and i take one where evey 3 months. Last period I was a little late because it was my first time on this new pill. Now my period is a week early. I know the first month pack of pills after my last period i did miss some pills on accident. 
im thinking my period is early because i missed some. the question is though will my period be off the cycle now. and i dont want to find out 3 months later it is. how would i fix it to make it back on the sugar back week?