Sayang, sakit perut dan pinggang awal pregnancy mmg common, tapi jangan ambil lightly okay, kena go to your doctor or clinic asap to make sure everything good with baby. A few of my mum friends yang 4 weeks juga complain sakit pinggang and cramping, tapi better nak check with doctor je to rule out anything serious. Mana tahu ada issue lain, kan? Jangan delay, just go see them, confirm everything okay. Take care of yourself!