What Does Severe Pain In The Abdomen And Sternum Indicate?

i hope you can help me back in 2005 i had a gunshot wound to the abdomen, long story short they removed 6 inches of intestines and had to put my bowels back together. I have had my gallbladder removed it was only functioning at 4%, fast forward to abpout 2 and a half yrs ago it seems as though everything started to really slow down and I began to have lots of stomach pain my stomach would bloat really badly and i woulkd have edema in my legs and feet now as of 3 months ago I have aloty of pain in my lower left abdomen exactly where the pain was when i was shot and i cant eat solid foods or its painful my actual stomach feels twice its size and ive used every laxative otc and rx wise including linzess and amitiza otc wise miralax, milk of mg,saline laxative, magnesium citrate ive done it all i feel swoollen more than full im feeling hungry constantly but if i eat its misery and takes miralax and milk of mag just to get a little feces out the drs at er told me i have too much fluid in my stomach but cant tell me why my endoscopy and colonscopy comes back ok other than severe gastroenteritis but thats probabably cause the food sits in my stomach too long no one will do the tests to look in my interstine and my bowels but im pretty sure the scar tissue has probably like my surgeon told me it probably would has wrapped around either my intestine or bowels also some days it feels like someone has hit me in my sternum with a baseball bat which i assume is where everything is running back up into even my mouth and burning me they have me drinking mylanta and lidocaine for that please tell me what u think i should do next or what u think I cant take this much lnger my quality of life sucks right now and im tired of the pain er sends me to dr dr sends me to er please help