Brief Answer:
there are many potential causes

Detailed Answer:
Hello,

abdominal pain can be caused by many disorders. Depending on the location of pain we can narrow down the list but not so much. More information is required to exclude disorders. For example the tests they've done in the ER. Will you upload the reports? Also there are some important questions to be answered. The answers may help...

Are there any other symptoms (like nausea, vomiting or anything else) ? Does the pain radiate elsewhere? Is the location of the pain stable or does it change every so often? Does he feel more pain when coughing or moving? Is there anything that makes the pain better or worse? Does he pass gas normally? Is the abdomen distended?

Since a doctor examined him, I suppose that no serious signs were elicited. Did they also order blood tests? Blood tests can be very helpful in the assessment of abdominal pain.

Please provide more details to help me understand his condition better!

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Brief Answer:
gastrointestinal hemorrhage?

Detailed Answer:
If he vomited blood then gastrointestinal bleeding is a serious concern. It could be Mallory-Weiss syndrome which is transient bleeding due to forceful vomiting, a bleeding peptic ulcer or other disorders. Upper gastrointestinal endoscopy is indicated and should be done urgently.

I can't provide any more details because the information is not enough for a deeper analysis. If you can find more reports or useful information, please upload them here or directly at my email address: YYYY@YYYY

Best wishes for a speedy recovery!

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