Hello!

Thank you for the query.

Back pain, upper left pain and groin pain can be caused by urinary tract stones and does not have to be related with your stomach disease.
With urinary tract disease you should notice frequent urinating and burning while urinating. Also fever can be present. Stones gives sudden pain, infection more constant and less intense pain.
Of course your gastric problem can cause upper abdominal pain as well. As you have severe emptying problem, you are more prone to chronic stomach inflammation, what can lead to stomach cancer. That is why you should have it checked as well.
Pain in the left upper abdomen can be also sometimes caused by large intestine diverticles. This disease is caused by chronic constipation.
Groin pain should be also checked with inguinal hernia. Especially if the pain appears while standing, coughing or lifting heavy objects and/or any lump in the groin is present.

I suggest you to have some tests performed. You should start with abdominal ultrasound, blood work and urine analysis. Upper GI endoscopy seems also strongly advisable. Your groin area should be examined by a surgeon and if any doubts, ultrasound of this region should be done.

Hope this will help. Feel free to ask further questions.
Regards.

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