Unfortunately TIA isn't easy to diagnose, in, fact the diagnosis is usually made from the story of the symptoms the patient gives.
At this stage, it'd be worth getting your risk factors for arterial disease assessed, and if need be, treated. (As it is for anyone your age).
If you wish to pursue the TIA route, you will need to chat to your GP who will then decide if you need further investigation- these may include blood tests, doppler tests and brain scans, via a specialist.
Each GP will have a slightly different threshold for referring, which may be influenced by your ideas, concerns and expectations.
Confirmation of TIA will be dimly viewed by aviation medical people.