What Is The Treatment For Gastritis?

Question : Hi I have never had any trouble with my stomach and acidity until two weeks ago. I believe I caught a nasty bug that only affected my gastrointestinal tract. It started off with severe pains in the gut which then ended up with severe pains in the upper abdomen. I had lots of abdominal distension and trapped wind. No diarrhoea and no vomiting. It came on abruptly and was so severe I needed morphine for the pains and ended up in Accident and emergency. They did blood tests but all that showed up at that time were slightly raised white blood cells. I have been left with severe gastric problems with a fist like tight knot pain in my stomach and excess acid. I struggle to eat or drink anything. I get lots of burping and wind pains which can radiate into my upper back. I feel out of breath walking, feel exhausted with a dull headache.i have no appetite which is unusual for me. I can feel the painful area/lump area under the diaphragm when walking and it's very tender to touch. Recently my doctor took more bloods and did stool tests and all come back negative. I did a home blood test for h pylori which was negative too. I'm currently taking a PPI to control the acid and gaviscon 3 times a day. What do you think could be the cause of these gastric problems ?

Dear Dr XXXXXXX Thank you for your reply. The PPI has taken the edge off the pains and helped with the acid burning feeling in my stomach but the symptoms have not eased completely. My doctor did thorough blood tests but I'm not sure if he tested the serum amylase and lipase levels. Any advise as to what might have caused these issues to come on so acutely ? What other tests would you recommend ? Thanks XXXX