Email your photos from within the iPhoto app and all will be fine. In addition, NEVER do anything with your library from the finder. Stay out! Forget it is there! If you do anything to photos or the library from the finder, you will lose photos, corrupt photos, etc. Just use the iPhoto app to do anything and everything that you want to do with your photos. Except, of course, if you use Photoshop or some external editor.