Side effects or something else?

I took a pregnancy test, and I was pretty sure it was going to come back negative considering I had just gotten off my period a few days before. But then a day or two after I got sick for about two weeks, I finally went to the doctor and she gave me a steroid shot to make my allergies subside. Since then my have become seriously sore, and my are larger, im in a horrible mood (side effect of steroids I know) but I'm pretty much paranoid that I might be pregnant should I retest or just wait till I start again?