HELP!!!

Hi! I am currently 12 weeks pregnant and have hypothyroidism (had this before I was pregnant). My current prescription is for Levothyroxine 112 MCG and my OB just now tested my blood to find out that my thyroid levels are severely off resulting in a new 150 MCG prescription. My concern is if my unborn child could have been affected by my severe under active thyroid being caught this late. I’m terrified!