Decreased Fetal Movement

🌈K

So I'm just wondering when I need to worry. Ive been super busy all week and it occurred to me as I was sitting down for more than 15 consecutive minutes that I haven't been feeling my son move as much. And I chalked that up to being busy, him growing and not having as much room, blah blah blah. Then I started thinking that I remember my daughter moving much more than him at almost 31 weeks. And of course I know each pregnancy/child is different. So I decided to drink some cold juice and lay on my left side, which I did for about an hour. And I got 2 movements, I wouldn't even call them kicks. His movements aren't as strong as I remember my daughter's being. Has anyone talked to thier doctor about this and if so what did they say? When should I worry? I would call my doctor but she's going to be out of her office tomorrow. How many kicks an hour should I be having at this time? This is my second child and I feel like a FTM all over again! Help?