How can I deal with my depression and anxiety?

I never used to be like this. I was always the happy little kid. Now, I'm a sopre in high school and things have changed. I have no motivation and I feel separate from all of my "friends". I get really depressed and have horrible anxiety attacks, to the point where I can't move and I just lay there in complete fear. I have bad paranoia and social anxiety, even though I do have plenty of friends. I feel like none of them are real, and I can't talk to them about what I'm going through. I just keep quiet, like nobody knows the real me. I've been self-medicating with various herbs and I finally have just called it quits. I'm in a very loving relationship, but I'm so scared my boyfriend will leave me and I'll be completely alone that I get jealous, paranoid, and clingy and won't talk about it. I just can't deal with anything in my life without breaking down and crying, then ending up in a panic attack over something simple. I don't know what to do anymore, this is tearing me apart. I'm just so hopeless. My family can't afford to pay for expensive prescription medications and definitely not a therapist. I need any help I can get, please... I'm sorry for sounding whiny, I just can't stand this anymore.