Twitching itself without pain is usually not a big deal. Cover the other eye once a day and make sure your vision is clear. Otherwise, see an ophthalmologist as soon as you get back. If vision becomes compromised, you need to find a way off the ship to get town ophthalmologist.
I'm sorry, there is no enlarged pupil. The guy I had look at it meant that my right eye looked bigger in general, because the left eye was twitching. I'm beginning to think I just have something under my eyelid.
also, I am working on a ship for the next month so I have no way of getting to an opthamologist until august