Kick counts?

So I just recently started to feel my baby move at around 19 weeks. It’s not super consistent but I can definitely feel it. Should I be concerned if I feel it less?? Usually he moves a lot around 10 every night and it’s definitely seemed to slow down the past few days but we just had the anatomy scan and he was moving a ton then and I couldn’t feel it. He was also super healthy. I’m just not sure when to worry about that since I just started to feel the movement a week ago.