NO, you are not over-reacting. Something is wrong. By the sounds of it (literally) something is loose. You're hearing the turbo more, the car won't idle right and something is rattling. Although I do have a bit of a rattle here and there.
Sounds like a loose wastegate, if I had to guess. These cars return wasted boost to the intake tract, yes? If so, the increased noise and the rough running would make sense.
Bring it to the dealer and insist they fix it. Bring it to another dealer if necessary.
BTW, why are you in neutral while going through a sharp turn?
Sophisto Grau / Oyster - Black Nappa, Anthracite Wood
ZAV, ZCV, ZCW, ZDA, ZDH, ZPP, ZP2, ZSP
Mods - M5 Grilles, BMWPedals Black Anodized
Heaven is where the police are British, the cooks are French, the cars are German, the lovers are Italian and it is all organised by the Swiss.
Hell is where the police are German, the cooks are English, the cars are French, the lovers are Swiss, and it is all organised by the Italians