The SDLTMS queued actions page will show you all the messages waiting (or currently) processing. 

The indicator for knowing which queued message is currently being processed is that it will have the server name that is currently processing the message in the Server column.

It is not always clear to know which processes are queued and which are actually processing when there are multiple pages, however if you order by the server name the messages being processed will appear at the top of the page.  If you refresh this screen a few minutes later you will be able to see which processes and corresponding identification fields have completed and which may be taking longer to process.

NOTE: the queued actions page captures a snapshot of the current processes in the queue, if there are multiple pages then the act of continuously refreshing this page from multiple users could add unnecessary strain to the server.  At times like this periodic monitoring (30 seconds / 1 min) is advised.