Battery Charge light flashing on Citreon C3 SX Tdi?

Hello, i purchased my first ever car last week, a 53 plate diesel Citreon C3. I was so excited i didnt check it over too much but im happy with it anyways.

But it came to this morning and i unlocked the car with the key. Before id even put my key in the ignition the red "Battery Charge" warning light was flashing, now im a novice, i looked in the handbook and all it says is if its lit permanently whilst engine is running then contact the dealer. Does it mean i need to charge the battery or something?

Please dont laugh at this question if it is something stupid, we all have to learn (and then laugh afterwards).

Just a note, the car started well (not as well as previous mornings but it was very cold) and drove as it should for about 2 miles to my destination, after removing the key the battery light was no longer flashing and the battery light was not lit whilst driving.

Thanks in advance