Ha! Yes, this is totally normal. The other day, I hopped on the scale and it said I gained 8 pounds. I knew i hadn't REALLY gained 8 pounds. I hadn't eaten 24,000 extra calories that week! The next day I hopped on and 4 of those pounds were gone the next day...another pound....and so on...and so on.
Our bodies do weird things. It can hold on to water for no apparent reason. We can get clogged up in our pipes (if you know what I mean).
So, don't worry about it. Try again in a couple of days. Drink plenty of water and I bet it'll be a different story.