One hard lesson to learn: usually when you're burning the candle at both ends thinking your hard work will be recognized by management and rewarded, it won't.

Sometimes they don't even notice, more often your output is their idea of baseline, and a budget is predetermined.

Depends largely on the organization, but I think this is the typical case.

Go home, have a life, or if you have extra energy roll it into a side project you can own.