Criminal Investigations: Can the Police Detain You After Determining That Reasons for a Stop Aren't Valid

My question involves civil rights in the State of: west virginia, My wife was pulled over the cop ran her plates after falling her for about 6 miles the reason he pulled her over was the computer said our plates were not registered, immediately during the stop he found out the computer was wrong and our plates and registration are in good standing. In my mind that should of stopped the traffic stop nothing else should of been legal and my high risk pregant wife whom is due any sec now and teenage daughter were being detained illegally, anyways the cop kept digging shining lights in car repeating asking if there were drugs in the car stressing her out like he was trying to get her to lie or something. We'll about 20min later he asked for her liscence and it was expired we knew it was, but reason she hasn't taken the test was we just moved to wv and she's high risk and about to pop so she can't take written and driving test in that condition, yea she shouldn't of been driving but I believe once the officer knew the reason he pulled us over was invalid the traffic stop should of stopped there, I'm fighting the ticket and im not a lawyer will u guys give me suggestions like, should I fight in principle since ticket only 33$ and how to I go about filing a motion for dash cam footage and motion to dismiss, this will be my first time EVER in a court room lol

Also we moved here aug25 2016 sin e then I got pulled over 5 times searched twice NO TICKETS until now, I live in a sorta bad area and I think we're being targeted when they find that out, but I know I could just be paranoid lol

Thank You for your time and patience,
Sean

Criminal Investigations: Can the Police Detain You After Determining That Reasons for a Stop Aren't Valid