With no vomiting or abdominal distension, it is possible that the pain your dog is experiencing may actually be coming from the back. As previously noted, abdominal pain and back pain can be difficult to distinguish from one another, even at times for veterinary medical professionals. As such, it may also be wise to also make use of our back Back Pain diagnostic tool.
That stated, it is not necessarily uncommon for a dog to have a condition that causes abdominal pain without vomiting or abdominal distension. Please read the Web-DVM articles below for more information on these diseases. If you still seek further information, please visit our Ask The Vet page to submit a one on one consultation with a licensed veterinarian 24 hours a day, 7 days a week.
Finally, also bear in mind, however, that in addition to these diseases, at this advanced age, cancer of the abdomen must be considered as a possible cause. Cancer can arise from any organ within the abdominal cavity, including the GI tract, spleen, pancreas, kidneys, or adrenal glands.