so i was just walkin along looting an ancestral tomb one day when an ancestral guardian unleashed his drain endurance spell on me. he attacked me a couple times, and when a fatigue was low, i like, fell down and my character was breathing heavily and stuff. this had happened before so i decided to try to find out what you were supposed to do to cure it. so (this is cheating but oh well) i used to the consol to transport to balmora, and i tried sleeping and waiting and stuff. nothing worked.

what is with the whole fall-down-breathing-heavily-and-don't-ever-get-back-up spiel? how is it cured?

Being knocked out occurs when your Fatigue reaches 0 during combat. This happens when, especially in the case of the ancestral ghost, they have a spell that drains your fatigue. Combined with the extra exertion of swinging a sword and/or running, this knocking out can take place quickly.

I believe damage is amplified when your opponent is on the ground, though this is just speculation.

You can't achieve unconciousness by exerting yourself naturally (running).

The only "cure" is to wait. The unconciousness passes eventually, as your fatigue naturally restores itself. If you don't get back up on your own, it is a bug.

Your fatiuge may have gone negative and you just need to wait until it restores before you can move again.

saldrex is right, you have gone in to the negatives on endurance points. This means your fatigue is lower then 0 because your endurance is the multiplier that creates your fatigue points... your best bet is to always carry around a few restore or fortify endurce potion and use that time to get yourself healed at the nearest imperial shrine. Actually to save time and money, you just make a ring that has CE forify endurance so you don't have to worry about your potions running out and stuff.

you could also have your endurence drained since that is what affects your rate of restoration. If you are very negative and have your endurence at 0 it could take you forever to get back up. -10,000 fatigue takes forever to restor from even with 100 endurence. A negative fatigue will not be rixed if it was drained and the spell wore off. It acts just like a damaging spell in the way that you do not recover after it finishes. IF you take too much damage to your fatigue you could e down for some time.

You could use the console and type in