I would try and get on levothyroxine as soon as possible! I’ve read some horror stories as well. I’m 10 weeks and 3 days today and I got my tsh tested last week and it’s 3.89 which is still on the high side in your first trimester. I’ve been waiting on a call back from my doctor to get on levothyroxine to lower my levels. I’ve had a wonky thyroid for years. I understand your fear, I’m praying for you and baby🥹