Hello, congratulations on your pregnancy.  Don't panic .. There are some changes which takes place in a pregnant females body ,because of the hormonal changes in the body .. Symptoms vary from person to person. If you have already got your dilated retina checked by an ophthalmologist , you don't have to panic . Regarding "Floaters" - As you are already talking about Liquefied vitreous gel, iam sure they must have explained you, in high sight myopic patients its seen . And that is not because of surgery.. in high myopic patient - gel form vitreous sometimes becomes Liquefied and that causes floaters...  

Don't worry, Go for yearly retina check up. These  symptoms are common in high myopic , in pregnancy there  maybe possibility of slightly increasing the flashes.

Flashes can happen due to number of reasons. Mostly they are non significant. Do not worry if you've already gotten checked.

You should at least visit yearly for your retina check up even after lasik. As in higher no. there is a chance of retina being weak. If there is any pathology in retina then it needs to be treated. Floaters in most cases are due to vitreous degeneration which are benign.