Have A Strange Sensation Around My Neck And Throat. Am Overweight. On Meds For Diabetes, High Cholesterol, BP. Suggestions?

I have been having this "condition" for awhile now. It's hard to explain, but I'll do my best. Whenever I am walking for more than 4 or 5 minutes at a time, I get this strange sensation around my neck and throat. It almost feels like I can't breathe or my throat is on fire or something. I always have to stop for a minute or 2 , catch my breath, breathe very profoundly then start walking again until it happens again. I have always been able to walk perfectly, and I enjoy walking. I've had this for maybe a year and a half now, but it started very slow, not all the time, only if I walked right after eating, or started doing a strenuous exercise, like vacuum the house. But now it is EVERY single time i am walking. I am starting a new job and it involves a lot of walking, and I'm scared I won't be able to do my job correctly. 2 factors to be considered in this matter are....I am a diabetic, and I am very overweight....but my weight has not changed in years!!!!!
I don't know what to do. I know it has to involve food and when i'm eating....because its worse right after i eat and worse when i eat certain kinds of food...like high in carbs, and starchy foods. It's really holding me back from what i love to do...walking! I take meds for diabetes, high cholesterol, and high blood pressure. I need to know what this is...so i can make it GO AWAY!!