5hiaa test came back at 6.5. I followed the food restrictions strictly the day of but not before. I did not stop medications which include dostinex, ibuprofen, xanax, (alprazolam) excedrin. Should I retake test?

Up to your doctor. This is very slightly above the reference range and many normal folks will be here. Whether to repeat will depend on your physician's index of suspicion for carcinoid. I would not be surprised if you have some imaging in your future.
Yes. In most labs, the normal range for 5hiaa is 2 to 8, so 6.5 would be normal. Excedrin contains caffeine, which should not be ingested during the urine collection. It would therefore be reasonable to repeat the test. One could also get a chromogranin a level, and urine serotonin levels, but these are both less sensitive and specific compared to the 5hiaa level.