However, depending on the context and nuance you want to convey, here are some other options:
* Informal:
* Je me sens mal. (I feel bad)
* Je suis déprimé(e). (I am depressed)
* Je suis au fond du trou. (I'm at the bottom of the pit)
* Formal:
* Je suis dans un état de grande détresse. (I am in a state of great distress)
* Je suis accablé(e) de tristesse. (I am overwhelmed with sadness)
The best choice depends on the specific situation and the level of formality you want to express.