This left arm pain can be from a muscle strain caused by the digging.
He does have a low diastolic blood pressure (if checked correctly) , he needs to rest and drink lots of fluids.
He would need to be examined b a doctor and have a baseline EKG, whenever you can see a doctor.
His current symptoms can be from exhaustion and not a recent cardiac event.
He needs to rest and avoid exerting himself and if he notices any palpitations / increased heart rate, chest pains, then he would need to see a doctor ASAP.
Kind Regards, Dr.Joshi
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