I asked this earlier but I would like a second opinion. When I lie down flat in my back I get a pulsating, pressure feel on my left rib. It only happens when I lie flat on back not on my side not when I'm standing or sitting. When I put my hand on my rib it goes away. Would this happen if it were a tumor? I get a little nauseated but I think that's just because I get anxiety from thinking hat the pain could be from. I got an abdominal ultrasound in January but it was a week before the pain started. Should I get another or does that answer my question? Thank you so much for your help and time. I really appreciate it.