2 month old plants below .5 oz. Felony being threatened.

My house was broken into, and in the ensuing police occupancy it was discovered that I had half built a grow box out of a dresser. Inside were two plants, each sprouted on Sept 8, with MAYBE 10 leaves and a stem. TN state law for growing 10 plants or less states the plants indicated are to be between .5 oz to 10 lbs.. The police took the plants, the grow box, a couple of pieces of paraphernalia, and some assorted things that have a tenuous connection to growing, i suppose. I should also add that they took some antique rifles that were in the house.. By antique, I mean the oldest being 140 yrs old, and none of them having been fired in at least 10 years. They are threatening me with charges for growing, which is a felony, unless i work for them as an undercover buyer.. I don't understand what felony charges they can bring against me if the plants weren't even big/old enough to be sexed, much less produce. I think I might need a lawyer, because it seems like the police are trying to scare me into doing their job for them.. Any advice will be appreciated.