My cervix is very high and I can barely reach it. I have used NFP for a few years, both for TTA and TTC, so I am very familar with my cervix

If you haven't checked yours pre-pregnancy you might not be able to recognize it now. Yours will probably either feel kind of firm like the tip of your nose or soft and squishy like your cheek. And of course there will be an opening in it. I usually check mine while sitting on the toliet using just my middle finger to gently poke around {wash your hands first.} Or sometimes standing up with one leg elevated {like in the shower.} I know some people say their DP's can feel their cervix, I just don't think mine wants to go poking around in there for that reason, lol!
As for the head, yep, just like NOS described! This baby's head is closer to the front side of my vagina and it seems like my cervix is tucked behind it.