Could be your providor.
Also reboot your wifi router -- hard reboot if you have to.
a really basic test is to hit the 'Num Lock' key, or the SHIFT key. There is a corresponding LED that will tell you that the keyboard has been pressed.
This requires a bare minimum of CPU functionality. If you hit SHIFT and you don't see the CAPs LED light, you are experienceing a HARD LOCK. If this key toggles the LED, you have a SOFT Lock.
This us not unusual, it can be caused by any number of things (including virus, malware, memory going bad, phase of the moon, price of tea in China, ect). Don't panic ... yet.
Hold the power button down for 4 seconds. This will tell the motherboard to kill the power. If you hold it less than 4 seconds, you are requesting that the processor turn things off. If you have a Hard or soft hang; the CPU is too busy comtimplating it's navel to listen to a mundane human.
Power the silly little guy off; and re-boot. Hopefully it comes up happy.
There is a WiFi disable switch on the side of the laptop. See if it has been enabled by mistake.
Next, click the Network Neighbourhood icon on the desktop, click on the 'View Network Connections' tab on the left, and double-click on the wireless connection icon.
See if it is enabled/ all ip addresses/proxies and protocols are correct. The problem is usually in this area.