Im no expert, but the thought of being on a horse and bouncing up and down sends pain straight into my head! Im assuming you also possibly injured your neck with the fall, have you had your neck checked out by a cervical specialist or chiropractor? i would think getting back up on a horse so soon would give you a massive headache, mess with your vision, create a lot of dizziness, and possibly nauseous. If you havent done much exercise in the past 9 weeks....which not many of us have that soon after, pushing yourself to get ready for a show will most likely set you further back in your recovery. Im 7 weeks out and attempted to do an hour of exercise a few weeks after my accident every day, and by the end of the week, i was so unbelievably fatigued and headaches were so bad, i could barely move and set myself back. Sadly, the prescription is rest. Take care of yourself and wishing you a speedy recovery.