There could be quite a few reasons why the OP has suddenly got problems.
Most of them have already been posted in this thread.
1 Any router or other device can and does go wrong through age , but mostly because components like resistors, inductors can fail.
2 The internet is a vast network, millions use it and just like devices it can and does go wrong.
3 When you ping a server [site] you are just pinging another device that might not be setup correctly or just bad server management
But the main problem is the network that ISP`s use it might need more attention etc, so I guess we have to contact them and hope , but either way as the internet gets more crowded there will be more problems I guess.
Also the computer [and the OS] can go wrong ,the PC is just another device and subject to the same rules as any other electronic or microelectronic device.
Edited by deleted (Tue 04-Oct-16 23:23:49)