Brief Answer:
Few more investigations- Gastroenterologist and treatment as outlined below

Detailed Answer:
Hi.
Thanks for your query.
Read the history and understood your problem.
To Recapitulate: Female / 28 - cramp like pain and uncomfortable feeling in lower and upper abdomen - sharps pains either side - nausea, light headed, dizziness, heartburn, lethargy, indigestion - diarrhea / constipation (is it alternating ?)- daily for couple of months -
-worse after eating and on waking up and before doing wee -
-tested for UTI - upper abdominal scan ( Ultrasonography or CT scan ?) - normal
-Wants answer - unwell and uncomfortable...

I would advise the following in such a young patient with so many problems at the same time:
Few more investigations:
Blood: CBC, Sugar, Thyroid function tests - very important,
Urine : already been done I suppose.
Stool: routine and microscopy
Upper GI Endoscopy and Colonoscopy.

If these investigations find the cause, to get treated accordingly.
If all the investigations are normal, then probably you may be suffering from Irritable Bowel Syndrome, the IBS.

I hope you had already consulted a Gastroenterologist for an expert opinion as you are suffering for a long time., if not please get an appointment.

Till then the probable course of treatment would be:
PPI and Domperidone for heartburn and nausea.
Antacid gel whenever you are empty stomach.
Probiotic and activated charcoal tablets.

The mainstay would be avoidance of any foods and beverages that instigate or increase your problem.
Control of the stress and / or anxiety as this is the causative or enhancing factor in many of the cases.

Some medicines are prescription based, hence you will need one and I am sure your Doctor and preferably the Gastroenterologist would certainly give you one.

I hope this answer helps you to get a proper diagnosis and get a plan of management for the relief and permanent cure.

Please feel free to ask for further relevant questions or if you feel that there is a gap-of-communication.

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