We've seen this happen to customers who choose the standard shipping method at checkout. Don't worry, though, as it doesn't mean your package is not on its way.
Standard rate shipping is coordinated between DHL eCommerce and USPS. DHL hands it off to USPS to complete the final delivery. What this means is, the USPS tracking may not show early movement until it gets to the final stages.
You can use this link to see your tracking info: track.firstmile.com