Susan, I am so sorry. Fatigue just sucks.
You could be headed for an exacerbation, many of the meds we take cause us to be tired and MS can cause sleep disorders which can also cause fatigue.
http://www.nationalmssociety.org/sit...tlight_fatigue
It's probably time to see your doctor. There are meds that
might help with the fatigue and a sleep study can rule out a sleep disorder.