How can I get more energy?

I have several factors playing into my "energy crisis". I currently have fibromyalgia, pms, and am tapering down percocet use from 10mg a day to 2mg a day. I am sensitive to caffeine so I can only drink a little. My Rheumy put me on Magnesium for energy but so far that has been a joke. I am also doing spring cleaning this week so I need energy. Sugar helps but my waistline doesn't appreciate it very much. This last week was awful energy wise, I have had so much going on and was so tired I could barely walk, no kidding. I think trying to up my dose of Neurontin was partly to blame (this was suggested by Doctor). Never again will I try that! I am desperately trying to get off percocet on a daily basis but the energy problem is really making it difficult. Please help, sorry for rambling. Thanks in advance.