What makes time fly?

Since my neck surgery, i have plenty of time to recouperate. before the surgery, i wondered what i would do with my extra time, after surgery? should i just lay in bed, like a slug, and feel sorry for myself, or should i push the envelope and hurry myself back into the mainstream ASAP? since my retirement, its been non-stop with things to do around my house. my time is really flying away. so, whats it going to be…..a slug for three weeks or my usual getty-up and go-go approach?