I have this problem with my Acer Aspire One netbook and this is the second time it happens. I recently bought a new charger for it because I thought the charger was the problem but that doesn't seem to be the case now. I plug in my charger and after a few seconds the blue power light with the light bulb symbol on it flashes a pink color and the light next to it that indicates that it's charging blinks a red light showing that it's not charging. Has anyone else experienced this before?
Are you sure your battery is flat? However, my brother had an Acer Aspire notebook and he had the same problem. The battery seems to be very low quality. He replaced it and after a few weeks it occured again. Then he bought himself a Macbook. I think you should get a new laptop.