My MacBook keeps making noises?

It's making a weird fan noise, I think it's coming from the right side of the laptop where you insert discs? But I'm not sure.. It wouldn't bother me too much if it was just the noise, but whenever the fan noise comes up, then the 'ball of doom' (rainbow ball thing.. beach ball? I dunno.) also comes up & then my laptop won't let me do anything... I end up restarting the stupid thing a million times . This started the day after I let my cousin watch her anime. URGH it's really bugging me, help! I can't do anything on it without restarting my laptop every 5 minutes,