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1.) nope
2.) keyboard settings>symbols and smileys> symbols on long press
Congratulations on your new phone. There's no Setting in stock Messaging app to have sound on "Sent", but I guess you can find a 3rd party app on Google Play that can do so.
To have the numbers on the first row of letter, go to Settings -> Language & input -> Xperia Keyboards -> turn off "Numeric keys"
You can also go through "Personalization guide in the same page for a visual control on how your keyboard looks.