How much sleep are you getting? Sleep is a big factor with fitness for me, anything less than 7 hours and I feel nauseous after a while too, especially if I go out a couple of hours after waking up.
Edit: Just read through properly and someone has already mentioned that, never mind!
Edit: Just read through properly and someone has already mentioned that, never mind!




. Also try getting more than 7 hours a night sleep, try for 8 instead, that may make a difference.