What does baby movement feel like 30-40 weeks?

I have a friend who nearly had a stillborn recently. She had heard from many people that babies stop moving as much before labor, as they are “getting ready” for birth, so when her daughter’s movement decreased majorly at 38 weeks, she didn’t think anything of it. Thank God she called her midwife and her midwife told her to go to the hospital, where she delivered her daughter. Something had happened with the placenta (not sure what) and the baby was not getting as much oxygen as she should have, which is why she stopped moving, she was preserving her energy. The doctor told her if she had waited until the next day, her daughter would not be here; she would have delivered a stillborn.

I am 25 weeks pregnant so this is unnerving for me. I am scared to the core of something like this happening. What does the baby’s movement feel like when you get further along, or close to delivery? Does it feel the same? Is it more or less frequent? How can you tell when something is wrong? What’s the difference between lack of movement when the baby is “getting ready” for delivery, and lack of movement when something is really wrong?