There are two possibilities:
1. It is possible you overloaded the circuit and a breaker tripped. Find your breaker panel and determine whether one of the breakers is in the neutral or off position. If you find one that has been tripped, turn it all the way off, then on again.
2. You may have locally tripped a GFCI. A GFCI is a receptacle in the circuit (usually in kitchen or bathroom circuits) that works like a mini breaker. Locate the GFCI(s) in the circuit and press the reset button.