Your description of Sprite is so sweet- "arthritic and bald, but bright eyed." I love these older pups.
I'm sorry she's having troubles. Ear flap hematomas can be so difficult to get healed up and I hate that antibiotics can cause tummy troubles even as they work to heal other issues. Maybe as the ear infection clears she'll do less scratching or head flapping or whatever is making that hematoma accumulate again. I hope things calm down for her soon.