I just laughed at your comment "no clue what to do with a little girl". I said that exact same thing when I was pregnant with my daughter. My hubby SAID he wanted a boy, the son ALWAYS wanted a brother, and I said "it doesn't matter to me but they want a boy and I don't know what to do w/ a girl". My son was 15 and I was so used to being with him, his friends, and teammates AND there were few girls in the family (as far as kids go). Then I found out we were having a girl....you figure it out....some is just being a parent, some they teach you, but you will figure it out. The one thing I did was I told family that I would tell them the sex once we found out as long as IF it was a girl they didn't go all crazy pink on me. I don't dislike pink but I hate ALL pink and my favorite colors are blue and purple (in that order). Besides, a little girl can wear any color. Then, we had trouble finding non-pink items because that color was "in" that year. Ironically, my girl looked great in dark colors (even more than in pastels). We broughter her home in a white w/ blue flowers outfit.
As for the health side of things, I didn't look at your age to determine "your generation" but just know that advances in medicine have come a long way just in recent years. Do all that you can to stay healthy. Talk to your doctor and express your health history especially as it pertains to females but don't stress on it. You and she will be fine.