I would recommend seeing a doctor immediately. Sometimes the ringing of the ears can be caused by blood pressure which can cause you to feel nauseous and pass out. You might want to have this checked. I would not wait to see if this comes back. I would make an appointment with your family physician as soon as possible.
No, you don't need to "see a doctor if it comes back".
You need a medical examination now, as of five minutes ago.
You need to go to an emergency room.
The modern emergency room, especially in a teaching hospital, is set-up to evaluate such problems.
There are many possible causes.
Fatigyue. Infection.
The sort of things that go away.
But there are goblins about. Things that go bump in the night.
One has to rule out an aneurysm, for example.
Fortunately we have the MRI, the MRA and the CT, inexpensive (relatively) non-invasive means to diagnose.
You need an in-person evaluation by an M.D.
pregnancy? stress? these symptoms can be so many things... If you felt better in the morning you could have been just too tired. I would recommend plenty of rest, cut the caffeine for a few days, but go see a doctor if it comes back...