Welcome to Orchid Board
What a pretty Phalaenopsis, great gift. I think it needs repotting in fresh medium, but I'm not sure if you need a bigger pot, you might need a smaller one.
With phals it does not always follow that repotting means a bigger pot. The new pot should be the right size to just fit the existing roots. You don't want too much excess medium or the roots will not be able to breath and that will suffocat them causing rot.
The choice of medium to use is wide and varies from person to person. I like bark, CHC or Hydroton/Lecca but some people like moss as you have at the moment. Moss is sometimes tricky unless you live in a dry environmental or are inclined to underwater.
The thread Sonya gave a link for is well worth a read if you are new to phals.