Hello there! Sounds like iphotos prefrences are messed up. Do the following to remove the prefrences file and that should fix the time issue.
Go to your mac hd icon then mac hd then users followed by your user. Then to library and finally to prefrences. Look for this file com.apple.iPhoto.plist file. Then move it to the desktop.Restart and open iphoto.
(On 10.7: Hold the option (or alt) key while clicking on the Go menu in Finder to access the User Library)