Hello and welcome to HCM
Appearance of sudden pain indicates some kind of nerve injury
Is there any history of trauma to your hand.
Trauma can cause a crack in the bones of the wrist and this can cause injury to the nerve.
Besides trauma an increase in pressure inside the carpal tunnel (a band like structure in the wrist) can cause pressure to the nerves in the carpal tunnel. This can occur in hypothyroidism
and diabetes mellitus
However, in carpal tunnel stndrome the symptoms are more severe.
You need to visit your doctor (orthopedician preferably) to get X-ray of the wrist.
Thanks and take care
Dr Shailja P Wahal