Had a serious concussion, blackouts are from concussions in your case. When your brain goes into a seizure (Its healing and rebuilding), you'll still function like nothing is wrong (Normal animal protections stay in place) but you're not really there. Really sounds like you gave yourself a brain concussion, which is a bruising of the brain banging around in your skull. You should get to a doc to see if you have a crack in your skull at the very least. A brain bleed can also cause memory loss and will worsen and YOU WON'T KNOW IT. Youll simply die from pressure and not even realize its happening.