Hello dear, I understand your concern. In my opinion when there is back ache along with abdominal cramping the preterm pains should be ruled out. The preterm pains are associated with cervical changes. So it will be best diagnosed by physical examination . Any associated symptoms like vaginal discharge,urinary complaints or any other should be seen. Because the vaginal infection,urinary tract infections,dehydration also might make the uterus irritable and lead to preterm pains. Nothing to worry.Once the cause is treated it will subside. Take rest.Avoid physical strain.Take adequate fluids upto 3 litres per day to prevent urinary tract infections. I would like you to see the doctor for accurate diagnosis and treatment. Hope this helps. Best regards...Dr.Srilatha