The state sent me a refund and this is November. I've already received my refund. Did they audit me?

Ohhhh they may send you a letter eventually, or you will have to call them and ask (find their phone number Thru their website).

What happens occasionally, is that someone makes a minor mistake on their tax filing, and the state eventually catches it when they start going thru tax returns in more detail at a later date.  

Something like this, many times, happens when a person a)  accidentally makes two balance due payments, or b) made some earlier state estimated tax payment that they forgot to put in their tax file, or c) had a refund in a prior year that they let the state keep, but forgot to include that in their tax file.  All these result in an overpayment by you, that the state eventually catches up with, and they send out the extra to you once they realize you overpaid.  Could be something else too you missed taking credit for, but if they don't send you another letter in a couple weeks, you'd have to call them and ask.why.