They don't "get rid of dogs" after 2-3 weeks to make room for new arrivals. If you're dog hasn't been adopted, I'm pretty sure that you can get it back. I hope that you get your dog back!
Yes, if the doggie is still there. They will probably charge you for it. After 2-3 weeks, they get rid of the dogs in order to make room for new arrivals. That depends on multiple factors.
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