I have tinnitus, just went to a ENT doctor and he couldn't find a reason for it, should I go to a neurologist?

Tinnitus. Tinnitus, unfortunately, is just one of those natural parts of aging for about 20% of the population. They rarely find a specific reason that can be treated. Most of it is just due to nerve degeneration (in the auditory nerve) or to increased prominence of blood vessel pulsations. The only treatment is "sound masking" where you use a source of "white noise" to distract your attention from the soun.
TINNITUS HAS MANY. Causes. But did they do any MRI imaging? Not sure you have to have it but a careful scan of the posterior fossa with thin sections and pre and post contrast imaging is helpful in some cases. Ask your doctor this is called 70559.