How can I distinguish between first Load of table and Load as a result of calling fnReloadAjax?

Hi
I'm using datatables 1.9.3 with the following configuration

 "bProcessing": true, "sAjaxSource": 'myservlet', 

I was wondering how can I distinguish on the server side if the table is being loaded cause of manually calling fnReloadAjax (after adding a row for example) , or its the first time the table is being loaded or user hit F5/Ctrl + F5

Thanks ahead,

Daniel.