saw Star Trek last night

ok so i saw the new Star Trek movie last night and im rather confused by it
spoilers if you havent seen it
So spock (Nemoy) is trapped 200 years or whatever it was in the past. Now his mother is dead and planet Vulcan destroyed. Young spock and kirk defeat Nero but now its all over we find spock (nemoy) is trapped in the past with his younger version and says hes going to help whats left of his people.
Ok now heres where i get alittle confused....
all the other events we know that happens IE spock died and kirk bringing him back/wrath of karn and all that. The bit that troubles me is since Vulcan no longer exists then doesnt this mean EVERYTHING we have had before doesnt matter? wasnt spock taken back to vulcan and his mother ect helped him remember who he was? but if those events happen again vulcan wont be there ect ect
I felt it was a great film but im just abit...lost...on the whole ending and how its ment to effect the previous movies/series. Or was this just a big screw up so they could make more prequal films??
spoilers if you havent seen it
So spock (Nemoy) is trapped 200 years or whatever it was in the past. Now his mother is dead and planet Vulcan destroyed. Young spock and kirk defeat Nero but now its all over we find spock (nemoy) is trapped in the past with his younger version and says hes going to help whats left of his people.
Ok now heres where i get alittle confused....
all the other events we know that happens IE spock died and kirk bringing him back/wrath of karn and all that. The bit that troubles me is since Vulcan no longer exists then doesnt this mean EVERYTHING we have had before doesnt matter? wasnt spock taken back to vulcan and his mother ect helped him remember who he was? but if those events happen again vulcan wont be there ect ect
I felt it was a great film but im just abit...lost...on the whole ending and how its ment to effect the previous movies/series. Or was this just a big screw up so they could make more prequal films??