I'm so scared!!

Iv been spotting brown discharge/light light blood on and off since this morning 10.30am. I'm about 4/5weeks pregnant. I'm scared I might miscarry. Iv got no cramping. Did anyone spot at first really light then later go on to miscarry or did u cramp straight away or did the cramping start later? I'm so very nervous and frightened. Please someone help me! I'm trusting in God and trying to be patient.