Yeah. I've gotten away with much longer tunes, and I've even been fooled by premature looping on some SNES tracks that I've timed (Cannondale Cup comes to mind...). Next time, try timing it to two loops (like what I did with the music I time for SNESMusic.org), then once you've done that, snip it down to one loop. And here's my render of the complete song: https://www.box.com/s/4zgjc009bvhq9iti9198
Fun fact: I intended on using Jxx effects to cut down the number of instruments I had to produce, but they came out slightly funny when I exported to .nsf. So I replaced them with instruments with effectively the exact same parameters. I didn't make pitch envelopes, knowing I had already finalized my track by then. The track starts out simple, as in an old-fashioned NES song, but I decided to add some fanciness the further along in the song it went. I had a working song name of "All Hail The Chip Champion" as a shout-out for Chip Champion, but I backed out of that name at the last minute.