As the other answers imply, "domicile" can be complicated. In addition to "domicile", there is a concept call "tax home".
But, the fact that you return to NC every week end and have an NC drivers license, almost certainly, means that you are an NC resident for state tax purposes. If you want to avoid paying NC tax, you need to "establish residency" in TN (register to vote, get TN tags and DL)
