Hi.
Thanks for your query.
The history is suggestive of a problem which is involving the lower chest and upper abdomen. 
I would advise you to go for a clinical / physical examination as this can detect better than the investigations ; for example the breathing sounds, 
rebound tenderness are the clinical entities and to be elicited by a Doctor himself. 
After clinical examinations the relevant investigations can be advised ; which h in your case can be :::
*X-ray chest to start with 
*Ultrasonography- it can detect the pleural fluid too as well as the 
gallbladder, liver and problems if the whole abdomen. 
* 
CT scan for confirmation 
* Routine blood tests including liver function tests, blood sugar
* Urine and stool tests
* Standing X-ray of the abdomen to see 
intestinal obstruction. 
* upper GI 
endoscopy if suspected to have acidity related problems. 
The treatment will depend upon the findings.