I'm sorry that your question wasn't answered in a timely manner. We don't have many avian vets on this site. Please let me know if you still need help. May I have an update on Marley Girl, please?
A bird that bobs its head up and down in a sort of pumping motion, beak open and then a purposeful delivery of partially digested food is regurgitating. This is something they would do to feed offspring or a mate. It’s done by some birds to objects (toys, mirrors, people) they are particularly fond of - especially if they’re in a breeding season, when a bird wants to please their owner and/or is of a nervous temperament. Regurgitation that is unusual enough for you to make note of it like you have, might be a symptom of crop infection/impaction.
Vomiting is more of a head “flicking” event. The bird will often seem uneasy, pacing or uncomfortable and although the head bobbing might be similar to the regurgitation action, it’s usually more of a shaking and the end result is a very splattered, sticky substance that may or may not include food. When there’s blood showing in the vomitus it may indicate esophageal or proventricular ulcers.
An avian vet (please see here: www.aav.org) will take a look into Marley Girl's mouth as part of a thorough physical examination looking for ulceration or abnormal growths and is likely to examine a swab of the oral cavity for abnormal numbers of either bacteria, yeast, or parasites.
Vomiting is a more serious symptom and seeing a vet as soon as possible is recommended. Important considerations include ingluvitis (crop inflammation) due to bacterial, yeast, and parasitic (Trichomoniasis, e.g.) infections. There are far too many possible diseases associated with vomiting to list here, but as in any case of illness, getting it evaluated, diagnosed and treated right away generally gives the best prognosis for recovery. I would be more comfortable knowing that Marely Girl was examined by an avian vet.
If she won't drink and eat on her own please consider eyedroppering a few drops of Pedialyte (or generics) every 20-30 minutes. Put the dropper gently inside her beak and let the drops fall into the bottom beak under the tongue rather than trying to get into the back of the throat. We don’t want to chance of her inhaling the fluid and developing aspiration pneumonia. Please heat up her environment to 85F so she need not expend excess energy maintaining her body temperature.
Please respond with further questions or concerns if you wish.