Carissa does not know how long it's been. She has not asked. She has not tried reasoning either from how often she sleeps or from how much progress she's made; she's pretty sure she's making progress at something of an irregular pace, to put it mildly, and she's not sure counting sleeps tells you anything if you're put to sleep with magic when your ability to make headbands runs out.
She finished it, the +6 headband. She finished it a long time ago. She was put to work on another one. This one is Splendour. Maybe she will just do this for all eternity; maybe it is, in Abrogail's revised consideration, the best use of her. Maybe she's dead and in Hell. She doesn't remember dying but maybe, after long enough, you wouldn't.
She succeeds, sometimes, at finishing a segment faster than she's ever done before. She only knows this because she isn't punished. Most of the time she just lets her vision blur and her senses dull and her world be consumed by the delicate weaving of the magic into the metal and she has no idea how well she's doing when she's stopped.