TombRaider Anniversary issue

Hi! well i just got the game. i ffinish the first level ( the mansion) but when i get past the level completed messages, it throws me back in the main menu. when i select resume game it just starts the mansion level again!!! its weird! and yes i got the full game not the demo...

stop playing the demo

I think i said IT IS NOT THE DEMO. get some glasses and quit trying to be a smartass.