I'm always having constipation and I feel full very fast. My lower abdomen feels bloated and I'm always burping. Sometimes feel breathless too. Why?

Insuff Information. I do not know UR age or UR med problems. I do not know what meds U take. If you are bloated from stool there is stool softener(Docusate Sodium). To clear stool quickly Milk of Magnesia (magnesium hydroxide) 2oz or 4 Tble spoons with 12 oz of water should clean U out in 6-12 hrs. I do not know enough about U to suggest anything else. U should see an internist and get a complete Physical and Blood tests as soon as poss.