If you go to the Launch tab and your Campaigns page, you will see a list of the active campaigns you have. Click the Stats icon seen here:
That will take you to the Campaign Summary where you can see an overview of how many emails you have Pending and how many have been Sent.
If you click on the Sent Emails tab you can see a bit more about your campaign and the sent messages so far, along with the order number and the date the email was sent. You can also see the actual message that went out by clicking the eye button:
On the Pending Emails tab, you can see when new emails are scheduled to go out and you can manually delete any messages. Just click the arrow next to the Order ID, click on the eye icon to view the message that's about to be sent or the trash can icon to delete the pending messages in the sequence.
Note that some orders will have the notification 'Waiting on Amazon to make the email information available', this just means we haven't received full confirmation from Amazon yet (most of the time due to a pending payment). However, these emails will be sent as soon as Amazon confirms the final payment was processed and your email trigger condition has been met.