Skipped period?

Claire • if the stars collide, will she relieve my soul?

I finished my placebo pack like two days ago and I haven't gotten my period. I normally get my period on like the 4th placebo. Also, Ive never missed my period while on BC before. What could this mean? Should I be worried?

FYI-- I'm currently not sexually active, so there is no chance I'm pregnant.