Need advice for severe chest pains

I do. I have acid reflex

If it's from POTS, laying down taking slow, semi-shallow breaths helps me.

It could also be a structural thing too like out of place ribs

Lavender oil on my chest helps sometimes. LiquidIV (or similar) and a snack will probably help, as pots chest pain will usually improve with increasing hydration, electrolytes, and salt. Talk to your cardiologist about this, because it's possible that switching beta blockers is causing it. When I was 17, my primary care Dr added another beta blocker to my regimine and it made me SO MUCH worse- my cardiologist wasn't happy with her 😅

Go to the hospital. They will figure it out

Go to the ER

How old are you? Is this related to another condition (GERD, anxiety)? This sounds like an emergency.