What category would I fall under?

Your best bet is to go out to the track first & see just what goes on. All tracks have E.T. brackets ranging from ET 1 to soemthing like ET4 (the slowest). If you've never drag-raced before, there's some rules & etiquette you need to learn first, which is why I suggested going there just to watch first.
Foregoing all that, assuming your Hemi is a stock 5.7 motor, my guess is you'd fall into ET2 , usually something like 12.99 to 14.00 e.t.