Increased thirst can be a few things. It may just be that you were thirsty yesterday, had you done anything the day before to dehydrate yourself?
Do you have any other symptoms? If the thirst continues, it wouldnt hurt for you to go to your GP and have a blood glucose level done. Dont panic it doesnt mean you have diabetes. Thirst is just one of the signs of it.
Some medications make you very thirsty too, have you recently started any new medication?
anyway, I wouldnt worry too much unless it continues, it could very well be just one of the things.
As you probably gather I am a nurse, so know a little bit about these things.I'm sure it will be fine