EC Side Effects

Andrea
I took Aftera (the Plan B generic, same levonorgestrel dose and make up) exactly a week ago and I'm still feeling crappy. Constant nausea is my side effect, but I can eat with no problem & have my normal appetite.  I've gotten small cramps that only last a few seconds, but don't occur often. My period is due in 3 days. My usual PMS symptoms are very mild to none: hunger/cravings & irritability, so I'm definitely feeling crappy right now. 
Has anyone else ever had side effects of EC last this long???