Is it legal to be pulled over because you have out of state plates?

I got off the freeway exit and a cop was sitting on the side of the road. He followed me for about 10 miles, another cop caught up, he hit his lights and pulled me over. He didn't even come up to my car for 30 minutes after stopping me. When he came to my window, I handed him my registration and license. He asked me why I do have a plate from another state. I told him I recently moved here. He said that usually people without of state plates are transporting drugs. He ran my license, came back to the car, told me to get out and they tore my car apart. Dumped candy out and poured drinks out onto the floor. They didn't find anything and let me go with no ticket or warning. Now, I can't find my wallet and my ID. I had $1300 on me, which is nowhere in my car. What can I do?