WAIT GAIN AFTER EYE SURGERY

So I just got surgery on my eye a couple of weeks ago, and they have me on a steroid to control inflammation. It is making me so hungry all the time! Like all I want to do is eat!!! I never used to do that. I started this medicine about 2 1/2 weeks ago and I have gained like 10 pounds, because not only does it make you constantly hungry it also makes you retain water weight. I am having such a hard time being ok with this, I am starting to exercise, which I never did before because I’m trying to keep off some of the extra weight. Does anyone have any suggestions about how to keep off some of the wait.