You're across the country from me but we're in the exact same situation. My first batch was an irish red and it fermented boisterously over a few short days. Since it was my only experience with fermentation duration, it became my norm. My second batch was a wheat brewed up this past Saturday, and two days later, there's no bubbles and no sign of a krausen. Even so, no need to be alarmed. You'll find the veteran brewers here on this board are pretty good at making sure you know that airlock activity is pretty much irrelevant, patience is key, and there's rarely a reason to worry this early instead of reaching for a brew and relaxing.
Yes, the initial stages of fermentation are relatively condition-sensitive, but 48 hours is too soon to be bothered. If there's still no action by Thursday, I may take a trip to the lhbs to pick up another packet of yeast. Until then, no worries.