Can't level up

I've managed to level from 1 to 2 nicely, but now I can't progress to the 3rd one.
It says to rest to meditate on your progress, but after I've rested nothing happens. The level bar is still full red, I can progress other skills but not level up...
Any reason?

I've got no mods installed except for Toggleable Quantity Prompt. 
My load order is very basic:
Oblivion.esm
Morrowind_ob.esm
DLCSHiveringIsles.esp
MorrowindTreeReplacer.esp
Morrowind_ob.esp
Morrowind_maps.esp
Morrowind Chargen and Transport Mod.esp
Morrowind Conversation.esp
ToggeableQuantityPrompt.esp