My doctor visits suck

Na

So I'm a first time mom and if it was up to me I would have an ultrasound every week since I found out I was pregnant lol I understand that's too much though. Anyway, every time I go to the doctor she listens to the heart beat with the same Doppler I have at home and asks me if I have questions. I don't know if my baby is measuring correctly, is her weight is good, I basically know nothing. When I ask her she says "about 3 lbs" as a guesstimate! Lady....how much does my baby really weigh! Maybe is just me, again I'm a ftm. I just need to know I have a healthy baby measuring accordingly!