So last night I fell off my horse. It wasn't a bad fall, he was basically walking. I landed on my back and I felt ok, just sore. I woke today with bad neck and back pain and soreness and stiffness in my arm and leg, which I expected, but- I don't know why I feel extremely nauseous and sick. I've never felt sick after a fall before. Is this nausea normal after an injury? I didn't hit my head and I was wearing my helmet. Thanks.