HELP! Please do not ignore

Has this happened to anyone before? I had unprotected sex on the very early on the 28th of December, took EC about 6hours later that day. Yesterday night(January 2nd) I had very bad cramps, leg pain and diarrhea. I took pain killers. I immediately did a pregnancy test and it was negative. This morning, I saw a little blood drop from my vaginal. Is this an effect of the EC? I’m I pregnant? I need any help I can get. Has this happened to anyone before?