Is dealing with panic attacks mostly just physical tricks?

This year severe anxiety completely wrecked me physically with heavy breathing, chest tightness, and sudden panic attacks that leave me totally drained. Lately the brain fog is finally clearing because I stopped trying to think my way out of it and started forcing my nervous system to relax.

Here are the 3 main things that are actually working for me:

Hydration and Sleep Baseline**:** Forcing myself to stay hyper-hydrated all day so dehydration doesn't trigger a racing heart, and cutting screens 45 minutes before sleep to finally beat the insomnia.

The App and Breathing**:** My girlfriend noticed how bad my heavy breathing was getting and suggested a breathwork app called Exhaleio. Using it to visually pace my breaths during an episode has been a game changer for stopping hyperventilation.

Vagus Nerve and Grounding Tricks: Sipping ice-cold water to shock my racing heart rate down and using the 5-4-3-2-1 grounding method the second my chest starts to tighten up.

Am I doing this wrong by just focusing on the physical side and relying on these tricks or is retraining the nervous system the actual way out? What worked for you?