super early pregnancy symptoms??

Is it possible to experience pregnancy symptoms potentially even before implantation?? I'm only a couple dpo, but I feel like I'm already experiencing aversions to smells that don't usually bother me...I'm at a church even right now where they're serving hot dogs with all the fixins and I feel sooooo nauseous!! I don't care for hot dogs, but I've never been bothered by the smell...the onions and chili are killin me too...is it possible to experience symptoms like this so soon??