Do I have to seal gl mosaic tile backsplash?

Hi, I have just put in a backsplash of gl mosaic tiles on the 12 by 12 sheets from home depot,on to the drywall withour backer board it came out great! But I went to ask about the sealer? It is very confusing grout lines are very small and a lot of the product applications come in a bottle with a little brush. But they all warn about getting on the gl/tiles. If I spend 4 hours sealing and it gets on the tile and looks bad my wife is gonna kill me!!! Does it need to be sealed?