Do I have undiagnosed depression?

I think I might be depressed. I am in a gap year between high school and university to save money for my education by working for a year. I moved away from my family to live in a bigger city for work. Since January I've just lost all motivation to do anything. I have days where I feel really down for no reason, and sometimes I just cry and cry.... like now. I lost my job as a waitress for messing up too many orders and now I don't sleep properly anymore, some days I sleep well into the afternoon and sometimes I just don't sleep at all. I also don't really eat anymore, I just don't get hungry, sometimes I'll make myself eat toast or chips or something but that's about it. I don't know any people in the city I live in, I used to talk to people at work, but I can't anymore, and my roommate doesn't speak English so we never speak, I'm really lonely. I did a quiz online to see if I was depressed, it said I had severe symptoms but I thought I should ask here.