So I Took A ECP Pill About The 17th Of

So i took a ECP pill about the 17th of November and now i haven't had my period since. Its now the 9th of Jan. I've taken four pregnancy tests all spaced apart nicely and the last one i took beginning of this week. They all have been negative. Just fifteen minutes ago i felt a sharp pain that started above my left hip and slowly over the course of ten minutes travelled upward. Finally a few minutes ago it disappeared.. Should i be worried about any of this?