lumps and redness usually come on because the gear contains too much ba/bb. Sometimes baking it for 15 minutes or so will help alleviate the sides, but mostly, just doing it more often in the same area will fix it. I only shoot it in my delts, so they are pretty use to most gear now. I know for a while it was pretty tuff and even today if I still inject high concentration test, it will screw my delts up for about a week.