Sakit bila bangun tidur tu memang common during early pregnancy, sayang, hormone changes and ligament stretching boleh cause mild aches, especially pagi-pagi. Tapi since you're only 4 weeks, best to mention it to your doctor or midwife during your first checkup so dia boleh confirm everything is okay and give you tips to manage it, like sleeping position or prenatal stretches yang sesuai untuk you.