I started feeling the baby move early on and then it stopped around 17 weeks, then started again a week later.I think it's normal to not have regular movement until about 22 weeks. :)
I'm 22 w and I feel the baby moving all throughout the day BUT not non-stop, only here and there. When I was 18 w I was feeling the baby moving only once during the night or so. It's not that the baby doesn't move, but its too small for you to feel it. When he/she starts growing bigger, you'll be able to feel her/him more.
I am 22 weeks and feel the baby off and on during the day. It started off slow around 19 weeks where I would feel it maybe 2-3x day and now I feel it a few times an hour. I cant wait to feel the bigger kicks and see it on the outside of my belly.
That's totally normal at 17 weeks, especially if this is your first baby.
I'm 31 weeks and feel the baby a lot, mostly in the morning and evening/night. At midday and throughout the early afternoon, he/she is pretty quiet - probably snoozing because I know that periods of sleep increase as delivery approaches.
Of course I'm far enough along that I'm at the stage where I can see and feel baby parts poking out, and if I prod them they move!!!