Bought my first road bike today, a brand new Trek 5200 (hold over) and I have been so excited to take it for a spin. I get home, take it out of the car, get suited up and head out the door. I walk up to the bike and realize the rear tire is COMPLETELY flat! Tried to put air in, but no go. There is a gash in the tube right next to the stem.

Normally this wouldn't be big deal, but my dumb butt bought everything but a spare tube! Is it common for this kind of thing? should I get a few spares?