You'll be safe (provided you *do* have ventilation), but just be sure you're not introducing a great deal of dust with the fan... Shcu777's post with the fan and filter is pretty neat-o! Also, januarytwenty's note that multiple light coats is the ticket.

If you've never sprayed paint before, practice on a few different scrap pieces to get a feel for the technique. Smooth, even motions, and follow through beyond what you're painting. Don't keep the sprayer too close. If you get drips or wet spots (puddles), you need to back off. Unless you have a narrow-angle nozzle for the sprayer, you'll be wasting a *lot* of paint due to overspray. That's normal (unless you have a narrow-angle nozzle )

The reason I thought the "sheet room" was a bad idea is more of a major fire hazard. Spraypaint goes up like a roman candle. It's nearly explosive!! Keep that (and all sources of ignition) in mind. Good luck, and hopefully show us some before and after pics!