Hi Wendy,
My dad, a former Buick dealership mechanic taught me this neat little trick to reset your electrical system. It has fixed many little issues, and should turn off the check engine light. Unless, of course, there is something that is causing a code to come up, in which case, check your engine.
Try this.
1) From engine off position turn the key so the full battery comes on (stereo should come on, but don't start the car).
2) Floor the gas pedal 5 times, all the way down, quickly.
3) Turn key to off position.
4) Start the car right away.
Hope this helps!