Deep breaths. Caaaaalm. Pick up the stitches and put them on holders and put it in time out to deal with tomorrow.

The damage
Okay, first, find the stitches that were dropped and give them a lifeline:


Now that logic has overcome the panic of my snapping yarn, let's get down to business! Let's load these stitches up on some needles, cut a length of spare pink yarn, and kitchner the shit of it (here's my favorite photo tutorial for this technique, by the way!)

Now it's time to weave in the ends. One end of the yarn goes into the pink row
where the stitches were grafted, and the other end I had to take up to the next pink repeat, where no stitches were dropped but the other end of my snapped tail leads. The last thing we want is for the other end of the snap to pull free and have no back up stitching to catch the loose stitches!
When I weave in my ends, I follow the stitch path of the knitting (rather than just looping through the garter bumps) to make it as unobtrusive as possible. This also helps prevent any weird bunching or clumping when you're working in colorwork and lace. In this case, it makes my ends function basically as though I had knit two strands together to overlap one end with a new beginning. After doing this for about an inch and a half, I cut my tails but leave a little out because I know when I block it, it'll pull some of that leftover length into the stitches when they stretch and I want to make sure I have plenty of overlap. Here's the finished product, no worse for the wear!
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