Am I infected by openDNS?

Alright, I just bought my brand new Macbook pro and I’ve had it for about a month now. I’ve noticed that at school recently, certain websites have been blocked. It isn’t teh blocking of websites like porn that has me annoyed, its websites like Neopets, Tumblr, Reddit, Gmail and Hotmail.

When I go to Neopets, for example, it says this:

This domain is blocked.

Sorry, www.neopets.com has been blocked by your network administrator.

This site was categorized in: Games, Social networking, Forums/Message boards

Contact your network administrator

I have no idea where this is coming from – I don’t even have openDNS installed in my computer. Is it a virus? Did I pick up some malware from somewhere unknowingly? I’m my own network administrator (well, my mother is technically since she pays the bill).

Computer Information
Processor 2.9 GHz Intel Core i7
Version 10.8.3
OSX Mountain Lion

What’s going on?