Her vomiting/dry heaving/goose honking is white foam when she drinks water otherwise nothing comes up but she continues to make the motions and sounds
Based on the symptoms you've described, it sounds like your dog is experiencing frequent vomiting of white foam, along with lethargy, difficulty breathing, and coughing. These symptoms are particularly concerning, especially given her age of 16 years. The presence of white foam can sometimes indicate an empty stomach or irritation, but when combined with the other symptoms, it could suggest more serious conditions such as respiratory issues, heart problems, or gastrointestinal distress.
The difficulty breathing and coughing, especially with the "goose honking" sound, might point towards a condition like tracheal collapse or another respiratory issue. When these symptoms occur together, it's crucial to address them promptly.
I strongly advise seeking veterinary care as soon as possible. A veterinarian will be able to conduct a thorough examination, which may include imaging or blood tests, to identify the underlying cause and provide the necessary treatment.
If you have any further questions, please feel free to ask. Thank you.