Ow by the way getting back to the topic at hand
Clean up your mess real good. Water don't epoxy grout like it does with the others.
And dont be scared, just be prepared you should have no problem, and most important READ and FOLLOW the directions given.Tape off everything you can and remove the tape soon after or the tape will be locked in by the grout.
And after a day or two later if you find a lump or two you can somtimes get it off carfully with a razor blade. Do it like you would clean glass.
And you might find a slight haze, You can feel this haze with your hand but its hard to see. I've used a product called Petra 7. You can soak a rag and rub away this gritty feeling haze.
Good luck.