I noticed after a day or two of lots of wiggles she'd take a few days to sleep. I'd still feel her stretching bit I wouldn't say it was actual movement like regular. She'd just wear herself out and take a few days to charge. It's totally normal. Now at 39wks (probably since 35) she's to big to do all that she did before. Now it's big slow movement as opposed to kicks and somersaults. It's sad :(
My boy is more active at night than during the day. As they get bigger I was told they can start slowing down too because there isn't a lot of room.
I go through the same thing with my little guy. Some moves may not be felt because of how the baby is positioned but also the baby does sleep. My son is more active early morning early afternoon and then slows down in the evening. If your worried you can count kicks (10 kicks in 2 hours) drink something cold, eat something sweet. If that doesn't make you feel better you can call your doctor or midwife. Hopefully this helps you. I'm also a ftm and was wondering the same as I'm almost 32 weeks