Parcel has been in transit for over two weeks

I purchased fragrances from [URL Removed] in the USA on the 9th of April 2015. The Parcel is bound for Windhoek,Namibia. The parcel was shipped with USPS on the 9th of April 2015. They claimed that the parcel was send with USPS Word Wide Premium Shipping and delivers within 2-7 business days..Tracking information show that the parcel departed Lusaka,Zambia on April 16, 2015 3:35 pm. It has been two weeks now and no further update on the parcel! Where is the parcel being held up? Are parcels in Transit supposed to take that long?<br> <br> Tracking number