What Causes Itching Bumps/rashes All Over The Body After Having Endometrial Ablation?

I had a endometrial ablation done on 12/30. I was under general anesthesia for the first time. I have been in "Twilight" state for a procedure years ago and I have had to spinals for c-sections but never regular, general, anesthesia. Late yesterday (12/31) I developed a rash over most of my body. It is in clusters of little red bumps and it is VERY itchy. Could this be a reaction from the anesthesia? Is it something that I should have looked at because of the recent procedure?