Also, if you are uploading from your computer using the "browse" function, you won't see your photo in preview mode; you have to go ahead and post it.
If you want to post more than one photo in one post, which is better than making several individual posts, each with one photo, the thing to do is to upload the photos to a picture-hosting service (photobucket, flickr, etc.) then copy the image codes (IMG) into your post.
(When you come back to post your photos, please don't start another thread--post them to this one.)