Anxiety's Getting Worse

I don't mean this in an edgy, woe-is-me, self-deprecating way, I mean it as a fact. Something I have to acknowledge. A while back I got diagnosed with generalized anxiety disorder. I'm not sure if that diagnosis suits me, it's just what I was given. My anxiety has ups and downs. Sometimes I feel way too depressed to care. Other times my mind feels wired and I feel awesome, but with that, my anxiety goes through the roof. And it's not even that I'm worried about something, or someone, or anything for that matter. I couldn't give a crap about what people thought about me, I don't really care how I look, I don't care about being embarrassed or social judgment. Yet when I'm in the halls and classrooms, my heart rate is through the roof to the point where It burns. To the point, it hurts to breathe, my mind reels, and I get dizzy and honestly, I just get this horrid overwhelming dread. I'm sick of it, It impacts my performance in class and it drives me crazy because I don't even know what I'm anxious about. I don't have anxious thoughts, if anything I just dread school because of the fact I know I'll feel that burning dread. I used to be medicated, but my psychiatrist and therapist stopped calling. (I'm pretty sure my mom secretly pulled me out) and for a while, it was manageable again, even after I stopped taking my meds. But now it's creeping up on me again. I just don't want to fall back into the whole I was in.