My horse tripped a couple days ago, need some advice?

Do not ride him again until you have consulted a vet or a chiropracter. Chances are he has pinched a nerve (if there is no swelling anywhere) and it is downright cruelty to ask the horse to work. He could have pulled a muscle or as I have said, pinched a nerve, but limping and inability to bend to a certain direction rather suggests that something is wrong.