Thanks for providing more information.
Firstly i appreciate your efforts to lose weight.
And as you describe most likely your symptoms are suggestive of nerve compression in spine which can cause such discomfort in right side of abdomen.
As per your investigations,chances of any abdominal issues are less.
Myofascial trigger point can be a possible cause.
In my opinion, i suggest to consult an Orthopedist for a clinical examination and undergo repeat MRI of spine.
You may also require physical therapy which can be effective.
You shouldn't lose hope and keep positive attitude.
Sometimes pyschological issues like anxiety,stress can aggravate your physical pain.
You should also discuss it with your pyschiatrist about your chronic pain.
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