Hello dear,I understand your concern.In my opinion the cramps in abdomen along with past history of miscarriage might raise a suspicion of miscarriage. But dont worry as it might be treated by treating the causes of it.The causes might be thyroid abnormalities,progesterone insufficiency.So i suggest you to get an investigations done to rule out thyroid abnormalities. Also duphaston is given in suspicion of progesterone insufficiency.Dont worry it doesnt cause any harm.If everything is normal the pain might be muscular in origin.Take panadol for pain.Take rest. Avoid physical strain and intercourse. Best regards....dr.srilatha