I got buckbroken by a sudden onset of generalized anxiety and panic attack disorder at around age 16. My parents had no idea what to do, it took just over a year to finally find a doctor who properly diagnosed me and referred me to a pediatric mental health clinic to explain to me that no, I'm not schizophrenic or have a mystery disease that's about to kill me. That the feelings of impending death are all just from a hyper sensitive nervous system that's malfunctioning, and here are the ways to cope with it and hopefully fix it completely. But a year of near daily panic attacks have done so much damage to a young impressionable mind that I still haven't recovered 15+ years later. Outside = panic is now a permanent association.
My biggest regret is not getting proper help sooner, not taking it as seriously as it needed to be, and giving up on myself multiple times. For the first two months when it was just the occasional borderline panic/severe nervousness during class, I was fully embracing it since it was an excuse to skip school and play video games. I had no idea it would eventually grow into something that would be a crippling disability that completely wiped out so many opportunities in life, as there's no opportunities to be had when you are unable to leave your house.
Now though after many attempts at recovery and relapse, I can function on some level with a constant lorazepam dose, constant meditation and stress relief exercises, constant lifting weights and treadmill running, constant going outside and working outside, but it's torture.