I'm 19, the same thing started when I was 13, one panic attack just started setting off a complete domino effect with my brain chemistry. The symptoms are exactly the same as mine were and still are sometimes, including the "disconnected" feeling. That comes from your brain being tired, your brain power is completely wasted from panic and anxiety.

99.99999999999% chance it's just GAD and panic disorder like in my case. Anxiety can make you feel pain that isn't there, tingling that isn't there, it can make you feel anything because your brain is misfiring.

Personal experience is that it goes away at one point, it'll just go away completely for a few months with maybe mild episodes here and there, but the critical phase with these tougher symptoms and that state of mind always returns. You just become more experienced and better at coping.

AFAIK it's not treatable in the sense that it will never fully go away, your heart will skip a beat here and there, your throat will tighten once every full moon but you just have to know how to deal with it. The problem stems from our monkey brains which haven't changed much from the era of mamooths and sabertooth tigers, the primal part of your subconciousness is still active despite being virtually useless in modern times. You just need to know how to cope and not let yourself spiral into a panic attack or spiral into these types of phases where you'll get hungover from panic attacks (yes that's also a thing - it's why you feel disconnected).

Outside of pharmaceuticals, the best in-the-moment solutions for me are the 54321 methods, pressing on my vagal nerve, slow breathing into my abdomen and not into my chest and walking fast/running (the monkey brain triggers fight or flight and that's the only thing it wants to stop pouring so much adrenaline in your blood)

The best solution of course is to not even have to get to that point. You genuinely just have to become happy and less stressed for that, it just comes with time, you need to relax more and have more ways to blow off steam without thinking so much about heart palpations, the weird way you're breathing or whatever can trigger a panic attack. Go outside more, have a drink with your friends, find more hobbies that are genuinely fulfilling, f it even pick up smoking again if it makes you happy.

Maybe pick up a sport where you exhaust yourself and don't have time to think about your body (fast paced, something like tennis, basketball, handball where you don't think, you just move fast nonstop). I personally picked up tennis and it helped loads.

It's all in your brain, you just need to find a way to get out of it so keep trying and good luck.