I have been running this cycle of Masteron for 2.5 weeks now, 1 ml e.o.d., and today was the first day I've had pain in the injection site.

This time around I remembered to swab both the stopper and my deltoid with alcohol, aspirated and used a 1" needle, with no pain during the injection. I also use a fresh needle for each injection.

My workout came 1 hour after the injection, which was also a shoulder/tricep workout. I'm wondering if this is the cause of the pain.

There is also some swelling in the area.

Please advise.