Welcome in H.C.M.
Regarding your query for pain in the jaw joint and a day after it extend to involve ear.I would like to say that you had enjoid in ocean a day before that may cause otitis externa
, a painful condition, but at the same time there is possibility of referred pain
to ear from jaw joint which is a well known fact.
So there are equal chances of both possibilities and this may be differentiated by clinical examination, therefore consultation with ENT doctor is must for dagnosis and treatment.