A dog was coming at me and started me. I was backing up and fell and hit the back of my head on concrete, presume around the occipital area.....slight red brusing on area....no loss of consciousness....no nausea, no vision issues....next seems ok....slight dizziness when initially getting up.....able to walk to house....put ice on area and pain seems to be slightly subsiding, have headache but had a minor headache prior to fall, hadn t eaten anything....should I be concerned??? Jaws seems weird though....