Home pulley injury??

I’m 8 weeks post-op from full tear Supra tear. I bought an over the door pulley for home use and last night as I was doing them I felt a pop and had pain and burning on the top of the shoulder (not where my repair occurred). I iced it immediately and went to bed, but woke up with pretty severe pain in the middle of the night so I took Tylenol.

Could I really have injured myself by being over zealous with the pulley? I bought it because I thought it would be foolproof, and my PT assured me it’s very hard to mess up a repair just by home exercises.