I feel like maybe I'm just not destined to make that tunic. I got a few more rows into it, and I realized that it's coming out too small and I'm going to have to frog it.
I checked my gauge a whole bunch of times before I started. I tried a lot of different hook sizes. The closest I got seemed to be with a J hook (instead of an I hook), but now I don't know if I'd need an L or M; I had tried testing my gauge with both before, and it had seemed too big. *sigh* Too much work and nothing to show for it (except about 8 rows of too-small tunic, which I will be frogging--not right away, though; it's too depressing).