I'm having a hard time breathing in my heart is pacing fanit started like 12 p.m. and still doing it?

ACS: Go and see a doctor today and/or go to an emergency room to r/o acute coronary syndrome. A family or friend should take you, if not call an ambulance. Don't wait.

Pacing fanit-racing?: I don't know what pacing fanit means but it sounds like you need to go to the er or minor emergency center to exclude atrial fibrillation or another arrhythmia.