week 13, no more progesterone :s

At my last Dr. appointment I was told that I can stop taking my prometrium. I am very nervous about it, but everything I have read says that the baby starts producing its own progesterone at 10 weeks. I took my last pill friday night. I sure hope everything goes okay! I thought about getting one more refill of my prescription just to be safe, but I'm sure that my dr. knows what is best.