Theodore is most likely having a reproductive problem and needs to see an avian vet (www.aav.org/vet-lookup) ASAP. The 'bubble' may be from a broken egg.There are no home remedies that are safe or effective.
While you are waiting for your vet appointment, increase the room temp (to around 80 degrees F (27C) if she can tolerate it - watch for overheating: panting, wings spread etc.), increase the humidity. If needed, move her to a plastic bin (makeshift hospital cage) with a padded bottom. Lastly, hand-feed juicy fruits,like small pieces of cut grapes or melon, and soft foods like warmed scrambled egg in addition to usual favorites. Offer plain water without any vitamins or other additives.
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