My Husband, Age 70, And I Just Returned From Cancun,

My husband, age 70, and I just returned from Cancun, MX. En route home he developed a sore throat, then cough, nasal congestion, watering eyes. In addition, today he has chills,diarrhea, nausea, vomiting. No fever. We have had our annual flu shot. He has been drinking tea, chicken soup, water and has been taking Alka Seltzer Cold, Robitussin/codein we had from a previous illness and CoricidinD tabs. Is this the flu? Comments on above meds? Do we need a visit to Urgent Care?