M.S.
I have taken it a couple of times of the years for various reasons. Basically, it is a high dose birth control pill. I think it has made me nauseous a few times, like sporadically, but it went away pretty quickly.
It is not an abortion pill, I would not take that, but it does stop implantation if it hasn't already occurred. The thing is that the sooner you take it, the more effective it is.
Really, each person will probably react differently, but it shouldn't be that bad unless you really react to bc pills.