First truth: you can’t do everything in a single practice session, but you can accomplish little things that will add up to big things.
Second truth: there are no shortcuts.
Third truth: learn to practice like a professional, it is more effective and much less stressful.
Gerald Klickstein, author of the book “The musician’s way”, is a valuable resource on professional work skills and stress reduction in the practice room. The link below is a good entry point into his world.