I downloaded a spam from facebook. I can't delete it. Can you help me?

[Alex]

I received a message from my friend and there was a link. I was stupid and I clicked on it. It downloaded something called "IAmWhore". I chose Eset to check it and it was OK. I double clicked on It and i saw my PC was doing something but nothing opened. Then I knew i have a problem. I opened back my facebook and my friends were writing to me that what i am sending them. Then I realised i did a big mistake. Now it was some weeks ago but it is sending it every week. At any time it will send to my friends spam to chat and to wall. I am desperate. I am thinking about new account but it will be maybe there again. ( I am sorry for grammar)