Not really. If you do not see a shopping credit at least pending at the 7 day point, go ahead and file a trouble ticket. It is VERY rare that something is not pending within 7 days. The only exception are some custom items like MyTwinn dolls.
That said, we have to wait until the 8th day with a lot of the merchants to file a dispute because they want to make sure that the transactions have time to post before they investigate them.