am I in trouble? (TN-related)

Hello

I've been working in the US on a TN visa for about a year.

I've been going back and forth to Canada without any problem.

however, I went to Europe a few weeks ago, and when I tried to enter US again (from EU airport), the CBP officer there ripped off my TN/I94, and told me that I had to file it again...

I told her that its not an I94, and its a TN visa... and she said she didn't care...

I filed a new I94 on the spot... on which she hand-wrote "TN".

I haven't told my employer yet...
I'm planning to leave my current employment in about a month anyway.

but I just realize that I need a proof that I've been in US for at least a year so I can avoid tax on my car when I go back to Canada... I was going to use my TN visa as a proof... which is gone...

Am I in trouble?

Of course you have a copy of every I-94 ever issued to you, right?

If not, well, canada needs tax money.

While traveling between US/Canada, you may use the same your I-94 to travel back and forth.
When you re-enter the US from other countries, you must fill out a new one --- they usually hand them out on the airplane.
Your I-94 is actually not your Visa --- it's a departure record --- your "Visa" status is in the Official's computer.
But - what you should do is send a copy of your new I-94 to the Immigration Lawyer each time it's reissued. If there is no lawyer, then give a copy to Human Resources or Payroll ---