88 yo Mom so tired!

My sweet mom just got her pacemaker 6/12/26. I’ve been caring for her at home and she is so so fatigued! I realize that all patients are different but is this exhaustion normal? tbf, she napped a lot before the insertion due to wild A-fib, but this seems beyond. She is eating OK, no fever. We have a call in to her doctor. Any help, encouragement, etc?