Weakness??????

i feel tired and weak in my legs a lot lately, usually when i havent eat in 3-4 hrs. usually i dont feel like this it isnt too extreme ,sometimes they feel like jelly, but i can still walk.i dont think its a cold/flu as i only sneeze a bit but i dont have a sore throat etc just sneezing and maybe some phlegm?aslo my taste is a bit weird, not gone,just odd tasting?