Should I be concerned?

So I’m almost 21 weeks with baby #2 & I have preeclampsia. I’ve had lots of complications this pregnancy like a perigestational hemorrhage and other little things. The last time I went to the ER was March 2nd due to bleeding which they couldn’t find out why I was bleeding (I’m assuming my hemorrhage has ruptured) and so they did a pelvic exam and said it looked like part of my mucus plug had came out and it was in my vagina. Well fast forward to now, at my anatomy scan almost 2 weeks ago baby girl was already head down and so low. I can feel her head down in my pubic bone & today I lost what kind of looked like my mucus plug but I’m unsure. Should I be concerned that her head is that low? It’s causing me so much pressure and cramps. With my first daughter she wasn’t that low until I was 35 weeks or so.