Since you were clearly not driving under the influence, then there should not be any DUI charges being filed against you.
If you were registered on the police radar gun as speeding, then a speeding ticket should have been issued to you. This is just a fine and does not carry any criminal penalties.
To find out about your car, you'll want to phone the police station where you were held, and ask for the number to their impound lot.
Then you'll need to phone the impound lot, and they can give you the information on where to go to pick up your car, how much it will cost, etc. There is a fee per day for your car being in the police impound lot, so the sooner you call, the better.
I do want to let you know that it sounds as though the officer was not acting within the purview of proper criminal procedure. For this reason, I would also recommend contacting the Internal Affairs Bureau in your jurisdiction and filing a report.
You can let you know:
(1.) The officer detained you, even though you blew under the limit.
(2.) The officer kept re-testing your BAC several time, even though you were under the limit.
(3.) Your car was impounded, even though you were under the legal limit.
(4.) You were never given any information as to the location of your car or instructions on how to retrieve it.
I hope that helps!
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