Hi ~ You certainly sound like you're severely depressed to me. Having fits of crying and despair, etc., are sure signs of severe depression.
I've been clinically depressed all my life -- well at least since I was 4 of 5 years old. I didn't get treatment until I was about your age cause my parents were too busy getting drunk.
If I were you, I'd talk to my therapist about this and describe everything that's been happening -- what triggers it, all your feelings, etc. You HAVE to be very open and honest with your therapist about everything, or else your therapy isn't going to work. I told my therapy everything -- right down to the nitty gritty. I had to or else I wasn't going to get well. I've been in therapy most of my adult life, off and on. I'm "off" now -- I guess I graduated. LOL
Best of luck Atuin, and let us know how things go, okay? God bless and please take care. Hugs, Lee