Wellbutrin and postings

I originally started on Prozac about four years ago but it didn't work so my doctor switched me to Lexapro. When I went for my next doctor appointment she noticed the drastic weight gain and noted it had been since I started taking the Lexapro so again, I changed medications. I'm now on Wellbutrin and have been for almost a year. I have been exercising, eating healthier, but am still gaining. Is anyone else having this problem. The doctor told me Wellbutrin did not have a reputation of causing wait gain but something is wrong. I also never thought about it until reading all the other postings. I am constantly having headaches and a very short temper. I'm ready to come off of it all together and just deal with the depression.