MarthaI do give my two SW CAH boys a shot whenever they vomit from illness. I have never taken them to the hospital by way of car or amulance for an illness. They have had stitches and a few minor broken bones. In my humble opinion you did overreact, but you do learn from each experience and every child is different, and you will have a better idea what to do next time. My kids are 5 and 8 years old.
Good luck to you.