Belly scare

So at my 39 week appointment my doctor measured my belly. I think it was measuring at about 37-38, which he wasn’t concerned about, but I was curious if anyone else measured small due to baby dropping or being low? He had me schedule a ultrasound just to check everything out and he kept telling me it was more just to get a look at baby and not really for measurements so not to worry but you guys know how hormones can make you worry like crazy! Back note, I was measuring kinda small for a few weeks, I’m 4’10 and have a anterior placenta. Baby is back to back with me and he’s super low feeling. 1 cm dilated 70% effaced