Too big isn't really a big deal. If you can ride comfortably with the saddle and bars as they are then by all means do, just bear in mind when/if you get another frame there should be some seatpost showing.
Generally this is due to smaller frames having a smaller toptube, which means less reach. So instead of having a small amount of seatpost and short stem, you have a loonger stem and more seatpost when you have a smaller frame.
Too big isn't really a big deal. If you can ride comfortably with the saddle and bars as they are then by all means do, just bear in mind when/if you get another frame there should be some seatpost showing.
Generally this is due to smaller frames having a smaller toptube, which means less reach. So instead of having a small amount of seatpost and short stem, you have a loonger stem and more seatpost when you have a smaller frame.