Depending on the length of your appointment, I would try to generalize your symptoms.
Tell him you feel spaced out, perhaps anxious. More than likely, they'll refer you to a neurologist. If they don't, I would ask to be recommended one. This is something that you'll have to consider based on your insurance and how much you're able to afford, but seeing a neurologist and ruling out things with an EEG and MRI can be very helpful. If anything, it'll help give you a bit of peace knowing that you don't have brain damage or any other serious condition.
I would also get your blood tested and see if they offer saliva tests. These will test for:
- Vitamin deficiencies.
- Red / White blood cell count.
- Platelets count.
- Blood glucose levels.
- Cortisol poisoning.
Some of these can cause depersonalization. Even if they aren't specifically the cause of your unreality, fixing the issues with your nutrition (and anything else you may have) will help you live a better life in general.
Honestly, if you have the money to divvy out, see both the neurologist and therapist.
The neurologist will help rule out things like aphasia, neurological degeneration, and other serious things. Don't worry, you definitely don't have these! It's always good to just check. The neurologist can also offer sleep studies, if they deem it necessary, and can also recommend you EEG and MRI like I said above. Overall, going to a neurologist can rule out the bigger and badder conditions, which is always something you want to do with a condition like depersonalization. I was elated to find my MRI coming back normal and I think many others would as well.
On the other hand, a therapist can help target the more common issues that would cause depersonalization. Anxiety, depression, or trauma - these are things that are very casual with unreality, so finding a way to handle that and better yourself mentally is a great way to go to treat this disorder. The therapist can also see if you need to go to a psychiatrist. If you need medication, they'll definitely refer you to one and you can figure out dosages for what you'll be given.