Swimmer's ear or wax. Swimmer's ear is inflammation, irritation, or infection of the outer ear and ear canal. It can be treated with drops; it is reasonable to try vinegar drops first before obtaining a prescription drop. If the ear is completely blocked, however, it could be from impacted wax. This can be softened with hydrogen peroxide then flushed out with warm water. If neither treatment works, see your doctor!
Swimmer's ear. If your ear is blocked 7 days after a swimmers (external) ear infection, it is likely due to debris from the infection and flaked off skin in addition to whatever ear wax (cerumen) was in the ear at the time of the infection. In the case of fungal ear infection, fungal elements, in addition to ear canal skin can block the ear canal. See an ENT for ear cleaning and appropriate ear drops as needed.