I was exploring a dungeon and ran out of magicka and it no longer replentishes. Also, all of my major stats are "red" like str, wp, agi,....

Is there an explanation for what's happening to me?

Look in your magical effects page, just after the spells, do you have a disease called Astral Vapours? If so, a cure disease should sort you out, maybe a visit to the Chapel is due.

Yes looks you've been fighting Dread Zombies do as zen1966 says.

You were right. The cave i was in had all kinds of undead weird types. One thing though, I got cured at the Chapel as you suggested but I don't understand where "magical effects page, just after the spells" is. I'd appreciate it if you put your finger on it :icecream:

Look at your spell lists, the last page, after on self spells, has all effects, including racial resistances, magical equipment, etc. Any disease you have is usually at the top.
If your attributes are red, but you have no disease, they are damaged, and a cure disease won't work, but an altar or wayshrine cures disease and restores attributes.

Looks like either you Intelligence got a server hit or your willpower is effected which regenerates your magica.

If you are on a pc press tap then magical incon (3rd tab) and magical effects (last tap).

Might I add, potions can do the trick too

Astral vapours is awful, had to spend weeks in bed just eating chicken soup.....AWFUL.....I think cure disease works, make sure you have some ingredients

Possibly one of my biggest complaints of Oblivion (vs Morrowind) is that you don't get the visible warnings about diseases and such. I remember becoming a vampire after sleeping to level up and realizing that I had been diseased for weeks without knowing. In Morrowind besides the icon notice, people would comment about it "ewww, get away from me".