Re: Text message sent Why no notification
The "Message sent" found in older devices is not found in Windows phones, presumably because the phone would notify you when the message could not be sent either as soon as the phone fails to send the message or after a predetermined time-out duration, whereas if the phone doesn't notify you that the message wasn't delivered after that time-out duration it is safe to presume that the message has been sent.
Alternatively, you can activate SMS delivery confirmation in your Messaging settings - but depending on your mobile service provider this may incur additional charges.