Brief Answer:
Phrenic nerve stimulation

Detailed Answer:
Hello,
Thank you for your query.
I'm Dr. Shuba Hariprasad and will be answering your query today.

Your symptoms indicate Phrenic nerve stimulation.
This nerve supplies the diaphragm, the pleura & pericardium (layers that surround the lungs and heart respectively)

An especially cold drink can stimulate this and pain can be felt at the left shoulder, left arm, between shoulder blades or even the right shoulder.

There is nothing to worry about.
I suggest that you keep the drink in your mouth for a few seconds to warm it a bit before swallowing.

Hope this helps.

Please let me know if there is anything else I can help you with.

Regards,
Dr. Shuba Hariprasad

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