I Have Recently Started Taking Tanzeum In An Effort To

I have recently started taking Tanzeum in an effort to promote some weight loss. I have had no reactions to the 30mg needles and my doctor recently up'd the meds to the 50mg. My first shot with the 50mg was the past Saturday. overnight, I thought I had gotten bite by a spider or some other insect and I have an area around the shot that is showing as swollen and red. VERY itchy. I have put cortozone cream on it for relief of the itch but it seems to be getting bigger in diameter and redder (at times). When my husband injected the 50mg needle, it stung the entire time. Could this be related? and what can I do about it?