Wa'alaikumassalam sis! Sakit ari-ari dan pinggang memang common masa pregnant, terutama bila dah 29 weeks, the baby's getting heavier and putting pressure on everything lah. But since you're also feeling it in your thighs (cabang peha), please check with your doctor or midwife soon to make sure everything OK , especially kalau sakitnya getting worse or ada symptoms lain. A few of my mum friends had similar pains dekat third trimester, and their doctors just reassured them it was normal, but each pregnancy is different, jadi better safe than sorry! Rest as much as you can, try prenatal pillows, and don't hesitate to ring the clinic if you're worried. Take care of yourself!