How sad to have had such an upsetting Christmas! At least the problem is relatively minor. I hope you figure out how it happened so you don't have future concerns. My sympathies on the expense of the emergency vet. I have come home from ours much lighter a number of times with previous pets (cats, birds). It is great that they are available though.
Lily AKC: CGC CD HIT CDX RN RA RE RAE RAE2 RAE3 NAJ NA; APDT: RL-1; CPE: CL1-R, CL1-H, CL1-F, CL1-S, CL1
Peeves AKC: CGC BN RN