He needs to go to the ER
Being a diabetic, this could be angina.
The fact that he got better is not necessarily a good thing.
He could get worse rapidly again.
Heart problems must be ruled out now.
Despite other possibilities.
Given that he is a diabetic, even if his sugar is in range, and even if his blood pressure is OK, makes not difference: he needs an exam and EKG immediately.
OK, so that is an initial answer….
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