With your iPad in portrait mode, tap on the Mailbox button at the top left of the email list. When you can see the list of inboxes and accounts, do you see an Outbox? If you do, are your emails in it?
This is a temporary folder that only shows up when there are emails waiting to be sent. If the your email's are stuck here then there is a problem sending them. Either your intreat connection was bad/slow when you sent them, or your outgoing email is hanging altogether.
Tapping the circle/arrow icon a the bottom of the email list should attempt to send them again.