When a Facebook account is hacked or taken over, the attacker almost always uses that account to advertise, spread spam, and spread viruses. If your Facebook account is making posts you did not make or you are getting complaints from your friends or followers about spam your account is compromised. Log into your Facebook account from the facebook.com web page and change your e-mail account password.
Applications you have granted access can post on your Facebook wall. To adjust what applications can post on your wall click Account, Privacy, Apps and Websites, and either remove the application or click the Edit Settings link for the application you wish to edit.
Friends also have the ability to post on your wall. To disable this feature click Account, Privacy, Customize Settings and uncheck the Enable box for Friends can post on my Wall.
If your Facebook password does not work click the the Forgot your password? link under the username and password login boxes on the facebook.com web page to have the password sent to your accounts e-mail address.
Alternatively visit the Facebook recover password page.
Visit the Facebook secure page
Finally, we'd also recommend visiting the Facebook secure page to help verify your account is secured.