Before we get into the complicated stuff, please check that you've not got the touchpad disabled. Look across the 'F' keys at the top of your keyboard for one which has got a touchpad symbol on it. In both of these examples it's F9
http://tinyurl.com/lc493rj
and
http://blog.drivethelife.com/wp-content/uploads/2015/10/disable-touchpad-button.png
but it could be a different key on your laptop.
Once you've found it, press it together with the Fn key. (The combination of those two keys toggles your touchpad on and off). With a bit of luck your touchpad will work again and you'll only have to sort out the problem of a dead mouse.
If you still get no joy, did you remember to make a recovery drive (on a USB stick, or similar) when you first got the laptop? It's something that we're all meant to do but that 99% of people (myself included!) never seem to get around to. If you've got such a drive you probably need it now. Otherwise you'll probably need to buy one on eBay.