My rhr is around 50 i have palpitations when i drink coffee. hr increases a lot if i have a heavy meal or beer (to 130+) and i have difficulty taking a deep breath and chest feels heavy when it does (more likely with beer).what could be causing this?

You would need to have a monitor on when this happens to determine if your heart is going into an abnormal heart rhythm, like supraventricular tachycardia or SVT. There are medicines to control SVT and there are procedures to get rid of the abnormal tract that is causing the abnormal rhythm. But, before it can be treated, it would need to be diagnosed so you should see a cardiologist for eval.