Hi...I Am A White Male, 52 Years Old, 6'-0'', And

Hi...I am a white male, 52 years old, 6'-0'', and about 258 lbs. I own a machine shop (fairly high stress) and spend most of my time behind a desk so not a lot of activity. After I eat at night my heart and more so my arteries feel like they are pounding hard. I also seem to burp a lot when this happens. This happens quite frequently and I have checked my blood pressure on a few occasions and just as an example the other day when it started I checked and it was 125 over 85, and my pulse was 65 so it seemed pretty normal. During my physical several months ago I had talked to my doctor about this. I did have slightly elevated blood pressure on the last couple office visits so he started me on blood pressure meds but it really hasn't helped the feeling that I get. He also had me do a stress test and everything checked out great. My blood work has been fine as I questioned him on possibly early stages of diabetes but he said no. Does anyone have any ideas on what this may be??