Hypothyroidism in the third trimester? Kinda scared!

During my first trimester my TSH levels were off and I had hyperthyroidism. It disappears by my second trimester and did not need an intervention. I’m 36 weeks and 1 day and judge found out I have hypothyroidism — subclinical. My doctor is having me come in twice a week until my elective c section. One will be my prenatal visit, the other visit is for an NST. He said that women with hypothyroidism can have babies who are growth restricted. I’m not sure how my baby can be. At 35 week and 5 days he is already 6 lbs and 12 oz! I’m freaking out now. I wish my prior OB had retested me ...