How is this MITM attack being performed and what steps can I take against it?

Today, when I tried to access the internet (google on HTTPS), my browser (Google Chrome) gave me the following error:

I am on my own home Wi-Fi, which has WEP. When I tried to reload google on regular HTTP, I got redirected to

http://ift.tt/1yw9ZBd term>&...

which gave me a 404 error. Sites other than google seemed to work fine.

I assumed this was a MITM attack and so I changed the WEP key on my router and rebooted it. However, minutes later, the error page and attack was back.

My questions are:

1. How is the attacker still able to connect to my wi-fi, even after I changed my router's WEP key? I don't think it's possible to crack a WEP key in minutes, despite WEP's insecurities.


2. How is the MITM attack being made? Specifically, how can the attacker insert themselves between my computer and internet servers?


3. How can I prevent this from happening, now and in the future?


4. I am still under this attack, now using tor. Can the attacker still read data sent over SSL through tor?