WHATS THAT SMELL??

if it smells like rotten eggs then your cat converter could be plugged up

I would say new brakes, new exhaust, but if it is getting worse and you are loosing acceleration. Maybe the brake caliber is frozen. Check transmission fluid, should be red and clearish.If brown and smells burnt, could be the tranny. If you have a warranty, I would bring it back as soon as possible.