It's the mail system. Chill out, take a pill, have a stiff drink, wait some more, have another drink and wait some more. It will arrive sometime. Not sure when but it will arrive. Sometime. Soon. maybe. Did I mention it was the mail system?
Expedited parcel to USA should be within 5 business days. I've sent several packages lately. Some take a few extra days. The post office supplied a receipt with a tracking number. Use that number at Canada Post - Mailing, Shipping, Marketing, Shopping, Sharing or www.usps.com and find out where the package is.