That's terrible! Dude, I hope you're OK. You should sue that sonofbaitch for medical expenses and pain and suffering. What the fuck kind of thing was that for him to do? IDIOT! Very sorry to hear this happened to you, Juho.
Did you suffer a concussion? This happens alot when one is knocked out by blunt trauma like you just experienced, doesn't it?
Neo-Nazi types recruiting at a party is really weird to hear about. Usually these types of groups recruit more subversively I would think. This reminds me of the movie "Higher Learning" with Michael Rappaport...
http://www.imdb.com/title/tt0113305/