I have the same problem.
I've had my iPhone 5S for about six months. Up until a few weeks ago, I could send photos from the phone.
This is what I would do:
-- Select a photo from my photo album.
-- At the bottom of the photo would be a little box with an upward-pointing arrow. Tap that.
-- A window would open asking if I wanted to send the photo by Mail, Message, Twitter, Facebook
-- Select Message, or, select Mail.
-- Window opened in which I selected addressee -- either message or email, depending on whether I had selected message or email.
-- Add address(es), add message if desired, tap SEND.
-- Hear a WHOOSH and the message was sent.
Now, I can send photos to other people via message. However, I cannot send photos via email. I try sending photos to myself or to others via email. Everything seems to work fine -- hear the WHOOSH -- but nothing shows up in my inbox. Try to send photos to other people via email, they never receive them.
I have made no changes in phone or email.
Come to think of it, about the time the phone started not sending photos by email, there was a software upgrade released. Could that have anything to do with it?
Thanks.