Permanent Facebook App?!?

[Mary]

I attempted to download one of those 'fake like' applications on Facebook yesterday. It was through a program called Likelo and the application name is 'Sony Ericsson Xperia PLAY'

Since then, it's been liking statuses across the world.
I've deleted the app, turned off the Platform, changed both my email and password and have changed the app's security to 'only me'.

It's acting like it's another page on my Activity Log, but I can't delete it!

Any help would be so amazing. Thank you!