What Do Breathing Difficulty And Pressure In The Chest Indicate?

This has been going on for some time now. Years in fact. I can’t seem to pinpoint what caused it to start, but it’s really causing me problems in my day to day life. I have had an echo, stress test, chest x-ray, holter and a zio. The cardiologist says I have pvcs and that my pulse gets low at night (50’s) and released me because there were no major issues. The problem is that I have several days out of the month (sometimes several a week) where I have to talk myself out of going to the ER. I have gone three or four times, but was sent home each time saying it was anxiety. I feel my chest pounding, I take my pulse with my finger oximeter and it is erratic. It runs low and I can feel the beating in my chest skip. I check my blood pressure and it’s in the normal range. I get extremely anxious and begin to worry that I’m going to have a heart attack. I am on a beta blocker and I take a 3mg alprazolam XR daily for anxiety. When these attacks happen I feel tightness in my chest, difficulty breathing, pounding, sometimes I’ll breakout in a cold sweat, sometimes tingly and lightheaded, and my anxiety goes through the roof. Sometimes I’ll feel a tingling sensation in my anus or testicles. I am incapacitated because I’m scared to do anything. The slightest thing in my chest scares me. I’ve had gastric bypass surgery around 19 years ago. I am still overweight. I take zegerid to help with acid reflux. I feel very gassy when these attacks happen and sometimes if I get in the right position I can open my mouth and not burp but instead it’s almost as if air is escaping. It makes a gurgle sound. I can do this for 30 minutes sometimes. Sometimes this alleviates the attack, other times not. I don’t know what other info to give. I’d just like help. My doctors act like nothings wrong and just brush it off, but it scares me to death. I don’t want to die and leave my wife and two kids behind. I don’t know if the one time I don’t go to the ER is going to be the one time I should have. I just want peace... can ANYONE help?