How Can I Tell If Baby Is Head Down & If Baby Is Anterior Or Posterior?

Ni

I’m currently 34 weeks with my 4th child. And sometimes I can tell that he’s head down because I have a heartbeat Doppler and the heartbeat is low. And I also notice too that when he has hiccups they’re low. Also how can I tell if he’s anterior or posterior? I feel movements super down low and maybe it’s his arms moving? Maybe it’s his head moving? Idk it’s so hard for me to tell with it being my 4th lol…