Mine used to sting like a really big bee the first month or so, but it went away. I use a rice filled heating pad that my hubby found at some store to heat my injection sites prior to the shot on my legs and arms. LOL, I have enough cushion elsewhere that there's no noticable difference if I use the heat or not.

The neat thing is that it's big enough that I can drape it over my thigh. For the arm, I can slip it under the armpit. I can then drape, lean back, and use the back of the chair I'm sitting in to keep it in place. Washable and microwavable too, which is always a plus.

If the brusing is happening a lot in the thigh, You may be too close to the knee. I've learned that I can't go past a certain point or I WILL get a bruise no matter what else I do. Lucky me, I have big freckles that I can use as reference points.

It took trial and error to find out which settings on the AI wouldn't cause me bruising either in the thigh and arms. For me, that would be around 6. While the more cushioned areas are around 8.

Hope things improve soon.