Self-assigned IP problems when using Ethernet.

[w00k3y]

Hello, everyone. I have a 13' macbook pro that has been working stellarly until recently. I went home from college for spring break, and suddenly the wireless internet was extremely slow. However, I now believe that the problem is my router since all other wireless connections work fast and good. anyways, in my dorm, we use extremely fast ethernet connections, but I have no access to the router to reset it. The ethernet conenction always worked great, but I went home, messed with my network settings and stuff to make the airport faster to no avail. I tried plugging my computer to my home router via ethernet, and for the first time, I noticed "self-assigned ip, will not be able to connect to the internet" So, I was like whatever. I came back to my dorm, and plugged in the ethernet. Same problem. self-assigned ip. I even tried my room mates ethernet connection, and it still says self-assigned ip. I've tried everything from renewing the DCHP lease, to resetting my SMC, and even deleting items from my library that I saw as other fixes. I don't know what to do.