Any idea?

I am 21 weeks tomorrow. During week 20 I was experiencing leaking and was monitored. Last night I had really bad Braxton Hicks and I stopped feeling the baby move (he’s been a very active baby). I went to my OB today to get checked because this baby normally moves 24/7. They told me his back was to my belly button and his face/stomach/legs/arms were facing my back. My belly button has now popped out and I’m feeling a lot of discomfort. I’ve had a very rough and complicated pregnancy from the start. Does this mean he’s head down?? Does being head down mean he’s positioning for birth? They told me I had to make it to 23 weeks for survival rate.