Do you mean "Sent"? Or does it say somewhere that messages are currently being sent?

If the messages are in "Sent" then they have been sent, and you're good to go. The Outbox in Outlook is a holding area for messages for which you have hit "Send" but have not yet been sent by the computer. For example if you lost connectivity, you could still write email and hit Send, but since you were offline, the messages go to Outbox until connection is restored, at which time the messages are sent, then moved by Outlook from the Outbox to Sent.

Hope that helps.