Asking for advice/experiences!

Who has had a baby that keeps flipping? I go to a lot of ultrasounds and my baby is head down one day and breech a week later & vice versa! It’s stressing me out because I’ll be 32 weeks tomorrow & he was breech yesterday but a week ago he was head down! I do have an ultrasound monday and Im hoping he’s head down. How long does he have to flip head down and stay? Any experiences on what happens if he doesn’t by a certain time? I’m nervous, my last 3 children stayed head down when they flipped around 20 weeks. Help me please im stressing.