It's completely natural to feel overwhelmed by the 40-week timeline, I was so anxious about each passing week. Just take it one week at a time, you can do this.
It's around 40 weeks in total. Make sure you get your thyroid checked regularly during these weeks, as TSH levels can fluctuate and affect the baby's growth.
A full-term pregnancy is technically 40 weeks, starting from the first day of your last period. Always consult your doctor to understand your specific due date and plan accordingly.
I used to panic thinking why it's 40 weeks when everyone says 9 months! But 40 weeks is normal and counts from your last period, so don't worry about the math.