I used to have a drinking problem and I’m concerned about past head damage.

One of my friends who I used to drink with suddenly texted me so in conversation I asked them if I ever hit my head. They said I did a lot and I would hit it pretty hard they even said I would sometimes do it on purpose when I was really upset. I remember absolutely none of this probably from the alcohol or hitting my head or both. Is there anyway I could confirm or deny damage? Or ease my worries. I stopped drinking that heavily probably about a year or 6 months ago I forget when