Nervous

As of tomorrow I will be 12 weeks pregnant and officially out of my first trimester. Tomorrow is also the day that I stop taking Metformin. I have been taking Metformin since September. I credit the Metformin to restoring my cycle and thus making it possible for me to be pregnant. So, why am I nervous? I don't want anything bad to happen when I stop taking the Metformin. I think it has been the factor in helping regulate my hormones. I hope the placenta is ready, in place, and kicking out the hormones. It will be nice not to have to take meds everyday at 815 am and 830pm. My cell phone alarm will be silenced. I know nothing bad will happen, but it still makes me nervous because it's something different.