Did you get the first one or the second? I got both of mine and the second one was the worst. Goes away after a few days. Don't do any heavy lifting and don't put pressure on that arm for a few days or so.
Injection site pain is normal. Mine lasted a few of days with each shot. 2nd shot made me feel tired for 2 days. Best to get the shots on the first day of 2 or 3 days off work.