ugh, hiccups. DS got them everyday, multiple times a day from somewhere about 20 weeks-ish. It was cute the first month. Then it got kind of old. It feels much like when bubs is kicking, but its rythmic- but not nearly as fast as a heartbeat. If your bubs does get hiccups in the womb, they will probably have them when they are born as well. DS was just a really hiccupy baby, inside and outside the womb.

I hope you did feel your bubs heartbeat, that would be very cool.