If you have a doppler or know someone whose doppler you could use for a moment, you can tell by listening with that. If the heartbeat is above your belly button, baby is breech. If the heartbeat is about even with your belly button, baby is transverse or oblique. If the heartbeat is lower than your belly button, baby is head down. But that's only helpful if you have a doppler.
My baby is head down, and I usually feel movements in my pelvis. I can feel her moving her arms and bringing her feet up to her face very often. When she was sideways, when I laid down, I could feel her head or her bum popping out of my side, and it was extremely uncomfortable, so I knew. My first baby was breech at 35 weeks, and I only knew because of the doppler - I still felt the movements down low, but they were kicks and not punches, which I couldn't tell the difference on at the time.
Hope you figure this out! If you're feeling lumps and bumps, perhaps baby is posterior (back-to-back) and should be facing the other direction. It's safe to go on all fours to help swing her around, and it can't hurt, but you have to do this for at least an hour at a time. It's a great exercise for getting any baby into a better position, though.