Wa'alaikum assalam! Eh, at 30 weeks, uri naik is quite normal lah, baby growing and uterus expanding, so it shifts position je. A few of my mum friends experienced the same and their doctors said it's nothing to worry about as long as ada no bleeding or pain, but honestly, best you check with your gynae at your next visit to confirm everything is okay sebab kat stage ni kena make sure placenta position is good for delivery.