Baby’s Movement

Hi all, I’m just curious, I’m a first time mom, and I just hit 28 weeks, I know this is around the time my OB said to start counting kicks. My question is, I feel like I don’t feel my baby sometimes, or if I do it’s very small moment, do I count those? And also, at what point should I be calling my doctor about it?? I think I feel him daily, but I just don’t know? Sorry if it seems silly to ask this, my next appointment is coming up on Monday, and I’ll be talking with my OB about all my anxiety, but just trying to see what to do before then! Thank you!