Hello, I'm at week 42 of my pregnancy. The doctor said it was week 37 …

Hello, I'm at week 42 of my pregnancy. The doctor said it was week 37 during my last ultrasound. However, my placenta ages earlier than usual around weeks 38-39. According to my calculations, it should be week 39. Usually, doctors consider and monitor pregnancies based on obstetric weeks. At week 42, if contractions don't start, they might stimulate me. Then it could become dangerous as water may turn cloudy, the baby could get hurt, and this is dangerous for him. Additionally, due to the aging placenta, there could be oxygen deprivation in the baby. I have a question: who should I believe? And how safe will the baby be? If I