I think it's just a major molt, her first.LOl. My advice about preening pin feathers,,, Do it every day, pick a time and let that be your time to do it. Mornings seem to be best with my older fids. The pins are very tender until they "mature" . Shaft is dark with blood ,which feeds the growing feather. The keratin sheath starts to crack and the end of the feather is emerging, like a flower blooming. You can usually start "pinching" that sheath between your nails. Start out near the end, away from the shaft. Slowly work your way down to base of the feather, the sheath should break apart and fall away in flakes. ( on a mature/ripe feather) . If she jerks away, squawks,bites,etc,,, that feather is not ready and you should check back on it tomorrow. My hen will show me where to preen and allows me to check to see if they're "ripe"yet. It's a very "Zen like " thing. I systematically cover my whole bird and we discuss if the feathers is ready. It's a ritual that will almost guarantee the bird bonding to you. I would get others in your family to learn how and join in. Once you learn how you can teach the others. Your macaw will be a well socialized companion.