Engaged vs. Dropping?

Ok, so my OB told me that baby was engaged at like 28 weeks. I'm now 33w/2d and I now see that he is lower. I thought baby dropping was engaging but is that not the case?

I've been having preterm labor contractions since 29 weeks and I'm on Procardia but I definitely have felt different these past few days. Here is a picture of my belly a week apart. Does it not look lower? I also think I had my bloody show earlier today but I'm not certain because I had my cervix checked yesterday. But there was a lot. 😷