Try drinking a Pepsi (it has ALOT of sugar) or Orange juice. As long as you are feeling some movement it should be fine. Remember the space is getting tight in there.If you are truly concerned call your doc. And now is the time for you to start doing "kick counts". If you don't know how to do these..Eat a meal wait a few minutes after eating and sit down and relax. Count how many times your baby moves within a 1 hour period. As long as it is 10+ she's fine, if not 10+ call your OB right away.
Babies can go through periods of activity and inactivity just like we can, BUT....when in doubt, get it checked out! Change in fetal movement is something you always want to get checked out, especially if you're feeling frightened - trust your instinct and get it seen to.
It's probably nothing, but always better safe than sorry!
update us and let us know what you decided to do, OK?