Battery indicator has an X, and charger light stays green,

My battery indicator at the top of the screen has an X inside it, and the side indicator when I press the button doesn't light up to show how much battery is left. When I plug my charger in the light goes straight to green, I can't tell if its charging or not because of the X in the indicator. I turned my laptop off and on again and its still the same. Also it sounds like the fan over-heater things (i'm so not tech savvy so bare with me lol) are going off loudly, (sounds like a hair dryer just not as loud) yet my laptop isn't hot at all. I've closed all applications and tabs so really, my laptop shouldn't be over-worked as it should't be doing anything.

Hope someone can help!