Continuing Stomach Problem Etc Etc

In the last month my stomach has been spasming..It's almost like it vibrates. It can be a sharp pain at times or constant vibration. You can literally watch it shake. I have a burning directly under my sternum as soon as I eat and sometimes even when I have had nothing to eat. Everyone thought I was just having panic attacks so I have been to the doctors twice in the last month and they said it was probably anxiety. My stomach bloats, swells as soon as i'm finished eating. At first, it was only in my stomach. Now it is back under my sternum and it literally feels like it's moving, almost like I can feel my blood flowing. I get dizzy, the constant stomach vibration has caused me to get no more than 4 hours of sleep nightly. I get like a tingly feeling in the back of my head and a slight discomfort in my throat and lower back pain, but the main problem is the stomach vibration. I can't excercise, walk long distances, pratically do anything without it acting up. I go to the bathroom maybe every other day...It has a strong smell but maybe that's normal. As i've said i've been to the doctors a couple times had blood work down, checked for hernia, and x rays they found nothing. This pain can be severe at times but mostly it's constant. It's kind of like my heart is beating through my stomach. It's just getting harder and harder to fuction a normal, daily , active college life. Any suggestions?