555 Timer won't run at calculated frequency
Firstly, the ceramic capacitor will likely be a LOT less than 10uF with bias on it, as the voltage across it increases it will drop in value. It would not be unusual to see a small capacitor lose 50% or 70% of its nominal value.
Secondly, you're drawing a great deal of current from the power supply (LED with no series resistor) and there is no bypass capacitor on the 555 pin 5 and negligible capacitance across the supply (only 10nF). NE555 (bipolar) even on their own draw big surges when they switch.
Try bypassing the supply with 10uF ceramic, bypass pin 5 with 10nF or 100nF, and add a second regulator and second set of batteries just for the LED.
Or use a microcontroller, even with the internal RC clock you'll get infinitely more predictable performance.