I would say wait until after the pg before seeing an optometrist. If you have noticed that your eyes have gotten a lot worse very recently then its likely that it is due to pg. I saw my optometrist for my regular eye exam but it was at the beginning of the pg and everything was just as it usually is. If you got glasses now they may not be the right prescription for after pg. After I had DS, a physio told me that it takes about 3 months for the relaxin to get out of your system and muscles/ligaments to return to normal.

Regarding the twitch, I was told once it was due to fatigue. When I had it, I had been doing way too much reading and was told it would take 3-6 weeks to settle down. If you're straining your eyes a bit due to your altered vision then I guess that could kick off a twitch too - unfortunately it sounds like a bit of a vicious cycle doesn't it

HTH