Had sinus headache after my flight then attended event , after im a bit stressed , feel pulsating/throbbing above left ear, same headache too. idea?

Fluid in ear?: Assuming that these symptoms have been present for less than a week, fluid in the left middle ear from the flight may be the cause and this may or may not resolve completely by itself after 2 weeks. It is possible also that you may have an ear infection. On the other hand, from your history, I can't rule out a migraine headache triggered by stress especially if you have a history of migraine.