You had the course of antibiotics before getting to know you are pregnant. Although the majority of them are not recommended in early pregnancy
due to side effects on baby; however, they can be used to safe mother's life as in your case.
So, do not worry about side effects on your baby. Pray God you and your baby will be fine. Focus on your pregnancy onwards, eat healthy foods, drink plenty of water and live healthy onwards.
All the best to you and your coming-soon-baby!