Download this and use it to check cpu temp - go to cpu manufacturers website and check specs. for your cpu model to see if it's in the right temp. range.
If it is getting hot after an enormous amount of use don't put it on something warm i.e. your lap, and use something small underneath to raise it above the surface it's on to allow air circulation.
If you have had it less than a couple of years and there's something wrong with it, you should take it back.