When you send a creation, a banner will appear at the top of the screen indicating that it was sent.
Also, you can check the My Creations page. Click the My Creations icon in the upper-right toolbar on the homepage:
Each creation has its stage, e.g., Continue Editing, Ready to Share/Send, or Shared.
If a creation has been sent, the status will change to Shared, and the list of recipients will appear below it: How to Check Your Recipient List?
Enjoy, and remember that if you have any questions, just contact us.