20 weeks pregnant with no prenatal care. Kind, helpful words, please!?

Hi, I am 17 and I just found out that I am around 20 weeks pregnant. I have not had an appointment yet, my first one is this week. Is it possible that I got lucky and my baby will be healthy? I haven't gained much weight, but I have a very active baby. I always feel he/she kicking and moving around. He/she is seemingly very healthy, I have done a lot of reading up online. Any helpful words?