Could i be depressed?!

Hello. I have been feeling really low the past few months. There could be a few possible reasons why this is, i am in community college right now and i really don't see the point in school. I originally wanted to be a teacher but wasn't sure if i wanted to do that, and now i just feel lost with school. The only reason on why i am in school, is to make my family happy, not myself. I eat kinda crappy food, but not always, i have always struggled with my weight, it all began when i was in high school, i just quit playing sports and just became more and more withdrawn from things. I have friend's but not very many and the friend's that i do have are okay but they are always telling me to change. I have become more and more isolated over the years and all i do now is just stay home (usually alone). I don't mind going out but i am not always up for it, plus i don't have a car so it's hard for me to get out of the house. Another thing is i have a desire to be with this older man, who tutors at my community college, (he is not my tutor though) and it's legal and all. Anyway, i was hoping something would happen between us and he would possibly ask me out because it was obvious that i was flirting with him, and i think he was flirting with me too, but i haven't seen him in three months and i have been kinda depressed about that. All i want to do now is just stay home, i feel so withdrawn and sad. The thing is though i don't really show off my sadness, i guess that's why people are clueless about it. I have been wearing more and more black to my outfits. I just don't know what to do anymore, i feel so lost with everything in my life. I sometimes have deep, dark thoughts wandering through my mind. Does this sound like depression to you?