One of the first things to look at to ensure that your pump is working properly is to check there is power going to it and then to actually test it under "normal" conditions, which just means that you should pour enough water into the pit to activate the float switch which should turn the pump on. Assuming that the pump did indeed come on and remove the water out of the pit, you still have something else to do which is almost as important as the pump actually working.
Go outside and see where the discharge location for your sump pump is. Hopefully, you'll see or know where it discharges and that that point will be far enough away from the structure, at least five to seven feet away, but here is an example where more is better, say ten feet or more would be ideal. If you cannot find the location, you might have to refer to any available blue prints of the home. If after all this, you still don't know here the sump pump piping discharges, you might either look for evidence of newer or older water staining on the foundation walls, near where the piping exits the foundation or look out in your yard for signs of depresssions where water may have eroded a portion of the lawn.
The take home message is this. Take care of your sump pump and it will take care of you. Don't wait wait until a storm hits, like the recent tropical storm Sandy, to find out it doesn't work. And for those who want to take their protection to the next level, consider installing a battery backup system. The benefits will far outweigh the costs. Wishing you all a dry basement!