I helped a friend lift a 200+ pound box and my shoulder has been going numb and hurting. Any solutions?

Pinched nerve. This could be a lot of things, including a pinched nerve in your back. A physician skilled in osteopathic manipulation can often provide immediate and sustained relief for this sort of problem.
See orthopedist. Its important to establish a diagnosis. Shoulder pain could be from the shoulder or referred. Common referred sources include: abdomen, heart and neck. Shoulder sources include: arthritis, labral tears, instability, tendinitis, rotator cuff tears, bursitis, painful bony spurs etc. Therefore proper diagnosis is essential to stopping the pain. See an orthopedic surgeon. Good luck!