Let me add that when I got my eye exam recently I mentioned I sometimes saw flecks in my eyes. The eye doctor told me that it is coagulated eye goo floating inside your eye (sorry, I obviously don't remember the technical term). It can be the sign of some eye disease so it's good to get it checked out.
Seeing spots is something you should mention to your doctor. It is probably nothing but better safe than sorry.
I used to get them about once or twice a year when not pregnant and with this pregnancy I have experienced that 2 or 3 times. It usually happens to me when I've had a bad headache or migraine. Or when I have not had enough fluids. Be sure you are drinking plenty. I'm not exactly sure what causes it, hopefully someone else knows. I was just told that I need to be drinking plenty of water.