I am using a prop/npp mix 100 mg of each per ml.(I am also adding extra prop alone in the same syringe) It is from a good ug lab that I have used several times. Injections total 1.5cc (1ml of mix and .5 of prop). This is my first time with prop. I started last week and out of the 5 injections I have taken so far, two of them produced large knots about the size of a golf ball with redness around the injection for a couple days. The other injections were ok. No pain durring injection....just the day later (and lasts 2 days). I know prop can be painful and produce swelling, but is the redness normal? I am very clean when injecting, my wife is an RN and does them for me so they are being done right. Any help would be appreciated.