I think you did pretty well. I would file a complaint against the department. If you are up to it, I would also FOIA all the communications related to your detainment. One good thing to ask is "why am I being detained?" This forces the officer to tell you you are not detained at which point you can leave. Otherwise he will have to come up with a bogus reason you can use against him later if needed. The only thimg I would have done differently would have been to continue open carrying. Is it legal to record in NH? If so, I would start recording whenever you carry. Good luck.