So how long after you hit your head are you out of the woods from anything bad happening. i it yesterday on a steering wheel pretty hard?

I'd say 72 hours.: However, if you have a worsening headache, nausea, vomiting, don't wait 72 hours to get medical care.. Other symptoms that concern me include dizziness, weakness in one of your limbs, difficulty focusing or double vision, forgetfulness. The list goes on. If you're not sure if you should seek medical care after a head injury, you should seek medical care. Best wishes. Dr. Anne