Sayang, some cramping and soreness when walking around a lot in early pregnancy is pretty common, the ligaments are stretching and hormones are doing their thing, tapi if it's persistent pain atau ada bleeding, kena check with your doctor just to be safe. A few of my mum friends experienced similar cramping at that stage, especially kalau dah banyak jalan, so you're not alone, but better to get it confirmed by your gynae supaya you can relax!