Swelling in shoulder and arm 3 1/2 months after pacemaker

I got a pacemaker June 20 on the left side.  My left shoulder (especially the muscles behind it) is sore and swollen and my left bicep and forearm are noticably larger than my right side. It's very tight and you can see the veins in my bicep and forearms. I had a venogram.  No clots.  My cardiologist says it's unusual but he doesn't think there is anything to worry about.  But it's been over 3 months and the shoulder and arm are swollen and tight and it's quite uncomfortable.  Do you think the guy put the pacemaker in wrong?  I go to the pacemaker clinic in a month and see the new electrophysiologist.  Should I wait that long?  Any suggestions?