15 weeks and still kicking!

I am now 15 weeks and 1 day along in my pregnancy! My doctor's appointment was this morning and Mark and I had hoped that we would maybe find out the sex of the baby, but no such luck. I go back in a month and then two weeks after that, we go in for the sonogram and will find out if we're having a boy or a girl! We still in the process of picking out names but I think we have narrowed it down to 3 names for a girl and for a boy. We also found out what time of blood I have this morning. I have never known what type I was but I found out today. I am o negative. Now, that being said, that means something very medicalish that I don't understand. Bottom line, I might have to get a shot sometime in my second trimester. Why, I'm not sure! If anybody knows and would love to explain it to me, I would be grateful! We covet your prayer during this special time in our lives! Have a great day!