21 years ago l was involved with someone l latr found out was a heroin user. all the years l have worried i might have caught aids off him. no symptom?

Routine screening: No worries. At routine check-ups, a patient should be telling her doctor about such worries and getting the usual screening. HIV screening is (and should be) for all adults with such risk factors. One screening test is enough for past risk factors, unless there are new risk factors between one negative test result and the patient's next check-up. One can call her doctor for a check-up appointment.