Excited, nervous and everything else.

So we found out last week by surprise that we were expecting. Though I'm excited and happy to finally conceive I'm a bit more worried than normal because I was diagnosed with hyperthyroidism two weeks before we found out. I was taking medication that I wasn't supposed to be while pregnant because no one caught it in the hospital. Now I'm worried about the babies brain development in the future since that's the main thing correlated with your thyroid. Any other moms dealing with hyperthyroidism and pregnancy?! I just need some comfort because this is my first child and now I'm worried.