Help!

Letitia • Pregnant with baby #1 ❤️
I have an ultrasound today, I'm 37 weeks and measuring at 33 but babies head is well in the cervix. I'm so worried that something might be wrong, has anyone had this happen before? Also I've been getting a lot of Braxton hicks lately my midwife said it can be a sign that I will go into labour soon. Can an ultrasound tell if anything is happening with my cervix ect? (Sorry ftm)