Brief Answer:
it doesn't seem to be of concern.

Detailed Answer:
Hello!

Thank you for posting your query at Healthcare Magic.

I read carefully your query and understand your concerns.

You don't need to worry,it doesn't seem to be serious.It is a contracture of your back and arm muscles.It may be due to physical activity,due to cold or it may happen if you stay to many hours in an uncomfortable position (like a bad sleep position).
You should try to relax and rest.Take a hot shower or apply some warm compresses.You should do some stretching exercises to stretch your muscles.
You can take an anti-inflammatory medication like Ibuprofen for 2-3 days .
You will feel better in a few days.

The stiffness in your arms and back is not related with your stomach problem.
Stomach pain may be due to some condition like acid reflux,gastritis,peptic ulcer.
You should eat healthy foods.Avoid fatty,processed ,spicy foods.
Avoid drinking coffee ,alcohol ,stop smoking (if you smoke).
Eat small frequent meals instead of 3 major meals.
If your stomach pain is persistent you may need to start an PPI drug like Omeprazole once a day for 2 weeks.If this doesn't improve your symptoms you may need to run an upper endoscopy for diagnosis.

Your feeling of head pressure that happen some times may be just a tensive headache due to muscular contracture or it can be triggered from anxiety and stress.It doesn't seem to be of concern.

Hope it helps.
Let me know if you have any other question or doubt to clarify.I will be happy to assist you further.

Kind regards,
Dr.Rovena Murati

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