I think I'm depressed?

I don't know how I would tell, and my mom doesn't exactly care about my mental health so I'm really stuck here. I realized not much makes me happy, or I'm not able to be happy about things or stay positive for a long time. I find that if I'm not distracted by something then I end up sad for no reason. I also find that I don't really value my life much anymore, I don't care what happens to me and I again don't know why. Today at school I just got sad for no reason, every second I was tearing up and I didn't even know why, I thought it was stress from schoolwork, but during art I just started crying I don't understand I still don't even know why I cried, or why I was sad in the first place. I feel so pathetic and I wish I knew what was going on. But then again if I had to take medicine to change my feelings id feel like some freak that can't control their emotions. I don't know what to do.