I Have Had A Severe Breathing Problem For Over Two

I have had a severe breathing problem for over two years now and the doctors can not find out what is wrong. I have hyperthoridism and heperthoridism but they say it does not stop me from losing weight. I now weigh 240 lbs and most of it is in my stomach. My dr. put me on Senna, stool softener and laxative. I have always ad a severe impacted bowel and had a bowel movement every 4-6 weeks. Three feet in diameter and 12 inches long. But now it is soft and I goes every day or two. The problem is I have severe gas all the time and my stomach is presing on my lungs and when my breatehing problem hits I can't breathe. My question is will a tummy tuck help? My doctor says the veseral fat around my organs are the problem and a tummy tuck would not help. Who is right?