I wouldn't trust your schnoz, quite frankly. More than likely, the rich smell you're noticing is a function of a cold engine.

If the car is stock (as you say), and the Check Engine Light is not / has not illuminated while driving, it's worth going through with the test IMO. If you fail, the printout will show where & what specific types of emissions are excessive. The diagnostic report itself will be a helpful tool to figure out what is wrong. And to be extra conservative, get the car up to operating temp by driving around a bit prior to going in for the smog check. You'll probably do fine.