Here's my best advice.
Lie down on your bed and try to relax.
Put your hands firmly on your belly near your pubic bone. What do you feel? Do you feel a hard round lump? That's good if you do.
If you feel a hard round lump, put one hand on each side of it and try to "wiggle" it back and forth. If it "bobbles" easily, that is the head. Congratulations! Your baby is vertex!
If you do not feel it right at your pubic bone, try slightly higher. Sometimes babies will be head down, but still "floating" and not engaged in the pelvis.
I have been OBSESSIVELY checking this baby's position through the last few weeks. Seriously, I do it at least 3 times per day. I have gotten VERY good at telling where the head is. I also have felt hiccups up high. At first I panicked a little bit like you did, but nope, when I checked the head was down. It was high and floating, not engaged in my pelvis, but still in the general area it should be. I think over the past few days the head has gotten a bit lower, and I felt hiccups in my butt (sorry if TMI!) the other day.
I just have to laugh... the *only* way to be SURE of a baby's position is ultrasound? OOOOkkayyy. I can tell you exactly what position my baby is in, and an experienced midwife can do the same with her hands. An inexperienced person might need ultrasound, but really it's not THAT hard to learn the difference in how a butt feels and how a head feels.
BTW, a few weeks ago at my appt, my midwife was feeling for baby's position. At that time the head was up, and in my left ribcage. She was feeling down low, and I indicated where the head was and said "Try here."
She felt, and agreed that indeed felt like the head. She then opted to do a very quick swipe with the U/S machine to "confirm" and amazingly the head was EXACTLY where I had said it was. I am my baby's mother, and it IS possible for me to know what is going on inside my body. After being pregnant 6 times, I would hope I have SOME clue.
Last week I had the very sweet but very green student midwife do my exam. She was so cute. She felt around on my belly, then put the doppler on my lower right side. Nothing. She wiggled it around... still nothing. I finally took pity on her and asked her to try another spot. As soon as the doppler hit my skin BAM, heartbeat. Without using any ultrasound imaging.