walking wont break your water, it will just help you during labor and after losing the weight
that is just an old wives tale, and dont walk one foot on a curb one not, it will kill your back and hips (i know someone who did that lol)
anyway some people go 2 weeks over their due date, im sure your fine, and like laura said the presure is probably because the baby dropped or somthing, which will help you dialte and efface
good luck, sorry for the rambling, i hope i made at least a little sence lol
~alicia~