Annecdote: Touch screen broke, then fixed itself... O_o

[LoneSnark]

Like you said, it seems water got in but took awhile to get out. Placing your phone in a dry warm place would have sped up the repair, such as in an oven that you had on low and then turned off (test the temperature with your hand first, if it burns then that is too hot!). Even then it should take a few cycles.

It needs saying that reflashing your phone was a bad idea. It was unlikely that any data on the phone had become corrupt, but it is possible that the hardware responsible for flashing could have been suffering from water issues, so flashing might have bricked your phone. You could have reflashed after the phone dried out, but you would have had no way of knowing if your efforts at drying it out were working without trying to flash each time.