I went to the doctor and he said i have a ear infection and a viral he put me on meds how long can a ear infection last on top of a viral?

OTITIS : It usually last 1-2 weeks depending on the infection. Longer if some aural discharge is present.

Variable: Ear infxns are usually viral-->supportive care (for pain & fever) + fluids & rest are most important, plus watching for signs of bacteria possibly taking advantage of local immunocompromise to cause infection. Like most viral infxns, these will usually resolve in a week (or sometimes 2). If bacteria come in, you need antibiotics, which usually work within a week unless the bacteria are resistant.