I feel too depressed to even eat, how can I stop this ?

For the past 2 weeks i’ve been feeling down. I haven’t been sleeping well and everything seems pointless. I also been eating a lot less, I don’t know where my appetite went. I ate only one small sandwich the whole day, and I never felt hungry, even when I woke up. I even feel too lazy/tired to eat. I thought this was ok since I want to lose weight anyway, but i’m scared it’s ruining my health. I feel too lazy to even make food so I just don’t eat a lot. I’ve been in my bed or couch for most of the time, and when I do get up or go out I just want to go back home and sleep. What do I do ?