It is hard to say because it makes no sense that the doctor would tell you you might have a torn pectoral muscle but then just send you to a physical therapist. Did they do any x-rays? Do you have any diagnoses?
Who owned the horse? You would likely not have a medical malpractice case but you could possibly have a case against the homeowner or horse owner, etc. You should definitely contact a local personal injury attorney. Good luck and get better.
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