Overworking is buffering?

I hear “overworking” being categorized as buffering. Are there situations when it is not? I have been working 3 jobs since October to pay off a loan, trying to get it gone and off my list of bills to be debt free. I’m not sure what the difference between being driven towards accomplishing a goal you set for yourself/doing whatever it takes vs. buffering would be here? Is it only if you are working to avoid something else? Thanks!