What Causes Swelling In The Neck With Difficulty In Swallowing?

I have had swelling in my neck for some time now difficulty swallowing sometimes a lot of problems breathing high pulse rate dose not go under 100 high blood pressure, pains going up neck and down arm also have pains in other mussels of body (arms, legs) as pressure builds in chest I get a stomach ache in the upper stomach shortness of breath walking across the room I had my lungs checked last year and nothing wrong with them. can anyone tell me what I can do? or what this could be ? please