Small chest infection on the right lung since saturday, how long will it last for as I feel exellent, I had a temp, cought but they ended 2days ago.

It depends . Pneumonia or infection of the lung tissues varies in severity according to the infecting agent, your age & immunity and time taken till the start of treatment. Apparently in your case it wasn't a severe case or your immunity and the early treatment kicked off rapidly or both. It is a good sign that your symptoms resolved quickly. Finish your meds & followup with your doc.