Kimbell,
This is my understanding and somebody correct me if I'm wrong..
You can not import any medicine to the US without a importation license. This includes controlled or non-controlled medicines....
You can physically walk over the border with a certain amount though.
If they had opened your package it probably wouldn't have been a big deal. They would tell you it is illegal, scare you and be on their way...
Since they didn't open it, they can suspect all kinds of things...
I dont know what you should do... Someone else here can tell you what to do if they come back...
There is so much mis-information out there about ordering meds online..
I do know it is illegal... Everyone takes a chance...
Good luck to you, and let us know the outcome.... Poco