Sayang, placenta position tu memang kena check dengan doctor je, especially something specific macam ni, kena scan proper untuk tau if it's concerning or just normal variation. I'd really urge you to bring this up at your next check-up or call your clinic now if you're worried, sebab 28 weeks ni penting to monitor. A few of my mum friends had different placenta placements throughout pregnancy and it changed, so don't panic yet, tapi kena confirm dengan doctor yang tengok scan you. Get it checked soon, ok?