Saying that you got back "$5 in exact change" would be odd because you normally expect to receive the exact amount of change back. Why would they give you more or less? Then they'd have to give you additional money, or you'd have to give them back some... So you only specify when something abnormal happened -- shortchanged. Interestingly, there's no opposite for that.
But as a customer you can give them more than the amount required and they'll give you change. That's part of the "service". Requirement for exact change is normally not assumed.
@freezframe: -- shortchanged. Interestingly, there's no opposite for that.
The closest term I can think of is the one I would use myself if I got too much change back – I've been undercharged.