Maybe it's the kind of thing that wouldn't have caused a concussion for a normal person, but -- given that you'd previously had a concussion -- maybe it gave you a concussion, or at least prompted symptoms from long ago to resurface.

Regardless, a doctor isn't going to be able to help you. The only scenario in which they can help you is if you had a brain bleed, and (given the impact you described) it seems clear that you don't. I would just treat it like a concussion for at least the next week, given that you have symptoms. You know the drill -- no exercise, lots of rest, avoid cognitive stimulation & exertion... I think magnesium is supposed to be helpful in the acute phase, so I would take 300mg daily of magnesium glycinate.