Talk to Gynecologist on Missed Period

Aoa Doctors!! My friend missed her periods due this 25 n shes afraid she might be pregnant.(its her first time) Although she has carried out her strip test at home n its negative but shes really worried as she doesnt want to conceive right now (her personal issues). Isnt there a medicine that could immediately bring on her menstruation? Pregnant OR not, just the medicine for periods? Without any future fertility risks? Also, she cant go to the hospital for a checkup so we are totally dependent upon online prescription. Kindly help us out. Please.