Anxiety and depression 😥

I've had anxiety and depression since I was around 14 years old and I am now 18. And at the beginning of this year it started getting so so bad. I'm not on medication and I haven't spoke to anyone about if expect my boyfriend. He goes to the ends of the earth to make sure I'm okay, and he has tried taking me to see a doctor but I just have panic attacks before hand, and we never end up getting there. I find it really damn hard to go out in public, I literary haven't had any proper friends since high school, I only have my boyfriend (he was my best friend during high school) so I only have him, which I am fine with but I always worry that maybe I'm the reason why I don't have friends.. 
I have panic attacks out in public, I sweat, get stomach aches, my heart races. I constantly think people are staring at me or talking about me. I am super shy and nervous, and I don't know how to be confident. 
I'm pretty sure I have separation anxiety when it comes to my boyfriend leaving for a few hours. We have been together for 4 years, and I trust him  more than anyone, but I can't help but think bad thoughts.. 
I have a really great family and a incredible boyfriend, but I can't help but feel depressed 24/7. 
I really need advice on trying to get help, when i don't know how to talk to a doctor about what is wrong, because even when I start talking to my boyfriend about what's wrong with me, I start breaking down and having panic attacks. I'm scared that if I go to a doctor and they say that I'm not even as bad as what I say I am. I'm worried about getting judged.. How do I find the courage to go and talk to someone? I can't take it anymore 😥