Pictures etc on your SD card you can recover, by getting the card out of your phone and then put the SD card in your computer.
Everything on your internal memory of your phone is however lost.
What probably happened is that when you dropped your phone the battery was disconnected and this "acts" as a soft reset.
And during a soft reset the phone goes "back" to the date and time of the last OS update.
Furthermore you probably did not use auto date and time setting so your phone can not adjust to the correct date/time and locks the phone.