Hi,

Thanks for your query.

Purple speckly rash as you call it can occur when there is a lot of dilation or bleeding in blood vessels around the eyes which over a period of few days turns from red to purplish blue and then slowly subsides. It can follow a blunt injury or a very severe bout of drinking over a few days. This should clear up on its own and there is nothing to worry since you say the eyes from inside are fine.

An allergic reaction can also lead to a similar rash under the eyes. You can check with him if he took any drugs or medications especially aspirin.

Now regarding pain in the left arm, various conditions could cause this. Common would be a muscle pain / trauma. Other less common reasons would be spondylytic and rarely would be heart related.
Muscle pain will be localized and increase on pressing, shoulder and spondylitic pain will increase on movement of the part. It would not be a bad idea to check his blood pressure inspite of his young age especially if the pain or a feeling of heaviness is extending on to his chest. Pain due to the heart cannot be ruled out but is a remote possibility in his case.

You may try some antinflammatory drugs (if he is not allergic to it) and hot fomentation over the affected regions. If the symptoms do not improve, it would be ideal that you seek medical consultation from your local doctor. On the outset, I do not find it a worrying concern as of now.

Hope this answer is helpful. Should you have any additional concerns, I am available to help you further. Do accept this answer if you do not have any further queries.

Regards.

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