Obgyn check ups

So I am 18 weeks & I feel like my ob appts are quick & they ask me how I’m doing and stuff & do the ultrasounds, but he still hasn’t had us hear the baby’s heartbeat just see it?? I’m not sure why? Also doesn’t mention the baby’s measurements. & it’s supposably a really good office their nurses & mid wives there but like I don’t understand? I’m sure these are things especially hearing the heartbeat I should of heard early on like in first trimester. I have a Doppler at home so I have heard it but only at home & it’s bugging me that I haven’t heard it at the doctors