I often have trouble with the muscle swelling or becoming tight and a hard spot often if I inject in that spot it willjust swell more and will leak a LOT of blood. Last night apparently it was too soon So injected because other sites had pip in my delt which wasnt quite ready and a good amount of blood came out i couldnt wipe it fast enough to stop it from dripping down my arm aspirated dont think i nicked a vein. No blood when aspirated I was just amazed at the amount from a 29 gauge half inch needle. there was no pain at the time