read the troubleshooting 3.3 master list to see if any of your problems is listed there: http://wordpress.org/support/topic/troubleshooting-wordpress-33-master-list
de-activate the "pop up domination" plugin if you have it:
- flushing any caching plugins you might be running, as well as server and/or browser caches.
- deactivating all plugins to see if this resolves the problem? If this works, re-activate the plugins one by one until you find the problematic plugin(s).
- switching to the default theme to rule out any theme-specific problems.
- re-uploading all files & folders - except the wp-content folder from a fresh download of WordPress. by using FTP or whatever file management application your host provides.