That's the complaining noise. Callisto only does it if I get too close with my hands or handle her. She's a strange bird. Sweet, never bites, but doesn't generally like being handled.
Since yours is a baby and is doing this frequently I agree with others that she probably is hungry. Good idea to get a gram scale and weigh her daily. You can get formula and feed her using a spoon or put some of the formula in a dish and let her eat that on her own. You can also moisten and soften pellets with some warm water and see if she will eat that. Don't leave the formula or moistened pellets in the dish for too long. Do this when you will be home so you can remove the formula/moistened pellets in a timely manner.