It's also been my experience that discount orchids often come in broken down medium. You can slip the plant out of the pot and check the vitality of the roots. They should be green/white. If they are brown and mushy, root rot has already started and you will need to re-pot immediately.
If the medium appears to be dense or soil-like, be very careful about watering; I'd err on the side of keeping it a little dry and continue to check the roots carefully. However, do not let it dry out completely.
If you need more humidity (which often happens in winter when the heat is on), put the pot in a tray of pebbles & water. Just make sure that the pot doesn't touch the water. The pebbles will wick water and create a little humidity micro-environment.