Brief Answer:
Need physical examination and investigations.

Detailed Answer:
Hello,
Welcome to XXXXXXX

I have gone through your query and understand your concern.

There are plenty of causes for abdominal pain.
We cannot clearly say the causes for severe or sharp abdominal pain or mild abdominal pain.
Some times chest pain also referred to abdominal pain.
Because severe abdominal pain can sometimes be from mild conditions, such as gas or the cramping of stomach. On the other hand, mild pain or no pain may be present with life-threatening conditions, such as cancer or early appendicitis.

Few important conditions are Pancreatitis , abdominal aortic aneurysm, Myocardial infarction, perforation in duodenum etc..
Beta blocker which you are taking may also a cause for your abdominal pain.

If you are my patient, i would start with history and physical examination.
Here i am need answer for few questions.
When did the pain start?
Whether it is related to food or defecation?
Whether it is relieved by anything like food or specific posture?

Then I will proceed for physical examination to look for the tenderness in abdomen, exact site of pain, any swelling or enlarged organ in abdomen.

Then depends upon the findings and on the basis of history i would refer you for investigations like Ultrasound abdomen, X XXXXXXX abdomen, Gastroscopy, colonoscopy , Electrocardiogram or other blood and stool investigations.

I will either refer or give treatment based on findings from history, examination and investigation reports.

Hope this helps.
Please reply for further queries.
Wishing you good health.

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