How do I fix my Twitter?

[Mac]

Sometimes (actually, most of the time) when I try to go on Twitter, it'll redirect me to another page, either to log in to Yahoo, go on this random blog, myspace, I don't know.

This has been happening ever since I clicked one of those stupid spam links they send you through DM that's like "haha is this you?" or something.

It's not a computer virus, so I see no way to fix it. It really p*sses me off.
If anyone's had a similar issue, please let me know how you fixed it?

And no, it doesn't work if I try to tweet from TweetDeck or anything, it just tells me it couldn't connect to the website.

[Robert]

Same thing happened to me!
download a free trial of "webroot anti-virus with spyware", delete the files that have infected your computer, then restart it ans start twittering!