Being doomed makes you a lot more vulnerable to instant deaths... Normally if you have fate smiles (or maybe just lucky is enough) and monster critically hits you, you're often left 1 hp instead of being killed. But while you're doomed (and in this case also cursed) you'll hardly ever succeed with that saving roll and will die instead.
Also you really should avoid all paralyzing monsters like plague because those are very likely to keep you paralyzed if they manage to paralyze you once (being paralyzed significantly lowers your DV and they'll ignore your PV a lot more often).
However that regeneration ability is nice and can be used quite safely to heal yourself between battles.