When you enter your tracking number and it says tracking status pending it means that the USPS or UPS or other shipping company has not scanned your package tracking number into their system.
It could mean that the shipping label was created for your package but the USPS, UPS or other shipping company has not actually gotten the package yet.
The tracking status pending usually goes away within 24 hours and then changes to package accepted or something similar.
Sometimes the tracking status can stay in pending status until you get the package.
USPS tracking is much less reliable than UPS or even FedEx tracking so you may not see tracking status updates as often as you should.
But the tracking status pending means that your package is gonna reach the shipping company soon or it may have already.
If it's been longer than 7 days and you have not gotten your package then contact who you bought it from.