|"Thanks Tubes, it's just that it has never put up a window saying another devise if plugged in to the laptop."|
The message has to do with another User accessing the network between your computers, not another device. If it's your own network and the wireless connection is Secure (protected with an encryption KEY or code), the other User can only be YOU.
If you are simply using either or both computers to connect to the router and to the internet, that does not involve the local or home network beteen your 2 computers - in fact both computers can access the internet fine without you having to have a local or home network set up at all.
It's only when you use or try to use one computer to connect to the other computer on your own local home network yo get the message while shutting down.
You appear to have software problems of some sort to do with your network settings that can probably be resolved by the tech support guys, but this is a weird symptom that may have nothing to do with that:
"Today I can't type on the laptop as the letters don't come up".
Normally we would suggest some things you could try, but it appears you don't have enough knowledge and that would take a lot of doing, so you are probably best off having them analyze the problems, especially since it is still under warranty.
However, you should be made aware tech people will often wipe the hard drive and re-load the original software if they can't figure out the problems in a short time - if you have any personal data on the drive you don't want to lose, you will have to tell them to save it for you so that it can be re-loaded and you'll probably have to pay for that service yourself despite it being still under warranty.