I fell in the shower and hurt my leg. It is kind of swollen today and it hurts to walk on. Should I see a doctor or wait it out a few days?

OK to hold horses. Not only severe leg injuries but also minor injuries can be painful to walk on , especially in the first day or two. As long as there is no severe swelling, exceptional bruising and pain out of proportion to the extent of your common sense appraisal of injury, you might wait a day or two before seeing a doctor. You can certainly remove all doubt and have it examined at any time.