Occasional contractions of the mild sort are usual at this stage of pregnancy
and unless accompanied by any other disturbance are relived by rest. Since you have a history of pre-eclampsia in your past pregnancy and these contractions are accompanied by pelvic and back pain
, you should contact your obstetrician immediately. As you also have a headache, your blood pressure as well as your uterine activity should be monitored. You could be going into pre-labor
as well. Please get further advice from your doctor. Take bed rest
in left lateral position and avoid anxiety. Wish you safe motherhood.