What do I do if I undereat in calories or consume less protein than I should on a given day? Should I overload before going to bed? Should I overload the next day? Should I just go continue on as usual?
You really cannot "fix" a diet mistake in one meal. Do not try to do this. Just eat your next scheduled meal and continue on. Each meal is an entity in itself.
-------------- If you don't stand for something, you will fall for anything....