Linny, I wouldn't worry too much. Babies are figuring out their patterns now and everyone has up and down days, where they are more active, and then just want to rest. As long as you feel movements at least 10 times a day, you're okay. You already know that some days are lighter than others, so try and figure out the days pattern to help ease any fears. And when it doubt, drink some orange juice, poke around, have something sugary, etc and see if that helps kick it up a notch.
AFM, today is my 3D ultrasound. YAY!!! It was supposed to be at 11am, but they called me yesterday and asked to move me to 1:30 instead because they accidentally double booked me, and they said they would give me a FREE DVD recording of the session. I was going to pay the $25 for it, but if I can get it free, I don't mind that. Turned out, my mom took the whole day off work and not just that time so she could be there to see, so it all works out.