I feel sick to my stomach a lot and when I lay on my stomach I feel like there is a knot up high by my ribs. Also, when I lay down I won't burp, but as soon as I sit up a lot of air comes out without warning or my trying. This has been getting worse for the last couple of years. A couple of years ago when it starting the doctor thought I had gallbladder problems and did an ultrasound. The ultrasound came back okay but when the tech was doing it she said she had never seen someone with so much air in their stomach. I hadn't had anything to eat or drink for atleast 8 hours before the ultrasound. What could this be????