Sayang, at 5 weeks pregnant, perut sakit especially on one side boleh jadi banyak reasons, bisa cramping biasa, bisa constipation, or bisa something else. The diarrhoea part pun kena check. Please see your doctor or go to A&E as soon as you can, okay? Jangan delay, sebab masa awal pregnancy mcm ni kena monitor closely. Better safe than sorry!