Could this really be concussive force?
 

I am planning on going to the doctor tomorrow but I am still somewhat in disbelief that I have been experiencing concussion symptoms the last few days from what happened to me New Year’s Eve. I was walking along the street in a crowded area with some drunk people around and it was cold so I had the hood on my hoodie up and could not see to my side (peripheral vision was blocked). I heard a guy to my left yelling to his friend and then all the sudden realized he had hit me in the left side of my head, somewhere above my ear. I never saw him coming due to my hoodie like I said. It stung for a minute but I didn’t think it was a really hard hit. He apologized and said he didn’t mean to hit me and it seemed like more of a glancing blow since it was not on purpose, although he may have been running, I’m not sure. I kept walking forward the whole time and didn’t notice my head really move to the side or anything or feel my brain move around (which I did before when I had a concussion 11 years ago).

Does it seem possible for that amount of force to cause a concussion even though I kept my balance and kept quickly walking straight forward the whole time?

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.