I'm off federal probation in 5 months I still may owe restitution my PO wants me to come into her office for an assement what should I expect? Is this part of what's involved in getting off probation? Or did I do anything wrong?

Yes and No, it could be a regular meeting, or it could be special because you owe money. One of the big questions will be how are you going to pay and set up a payment plan.