When a character gains a negative level from any source, what is the narrative effect of that negative level? How does the character (re)act, how do they feel? Does that differ for various ways of getting negative levels?
From the rules as written, the in-game effects of negative levels are as follows:
For each negative level a creature has, it takes a cumulative –1 penalty on all ability checks, attack rolls, combat maneuver checks, Combat Maneuver Defense, saving throws, and skill checks. In addition, the creature reduces its current and total hit points by 5 for each negative level it possesses. The creature is also treated as one level lower for the purpose of level-dependent variables (such as spellcasting) for each negative level possessed. Spellcasters do not lose any prepared spells or slots as a result of negative levels. If a creature’s negative levels equal or exceed its total Hit Dice, it dies.
It seems like these effects are pretty severe, especially when you take into effect the spell needed to remove the effects: Restoration, which has some considerable casting requirements, and notably removes all exhaustion, fatigue, and ability damage to one ability for lesser casting requirements. With the various effects that Restoration can remove, it seems to reason that level drain is simply a more extreme version of the other effects.
I imagine negative levels could potentially be different if granted by different sources. In a recent game a character returned to life via Raise Dead, which grants two negative levels. One of those negative levels can be removed by Restoration, but Restoration says a second casting needs to wait a week for the other negative level. In that week between, how should that character react? Are they too exhausted to adventure, or provide labor for various downtime activities?
Should characters who gain negative levels through other means than being brought back to life act in different ways? My experience with negative levels states they mainly come from death effects – either the touch of a dangerous monster with ties to death, or from dying and coming back. These all seem to have a common flavor origin – the touch of death lingering on a character.
I'm interested in mainly official answers that I could point out to a DM who may not let characters take specific actions during this week period. Barring official answers, any well-supported answer is appreciated.