I have arthritis in my knees as well as water on my left knee. i was told to keep it wrapped and use and ibuprofen/tylenol if necessary. how long should it take for water on the knee to go away? im also in physical therapy?

First at your age to have arthritis is unusual . You could have a biomechanical Malalignment having a large Q- angle and thus disfunction of the knee cap or patella. A problem you probably have had most of your life and difficult to participate in sports. A podiatrist trained in biomechanics can prescribe a custom orthotic that will help when ambulating.