Hi there, pregnancy is not the only reason for delayed periods. Stress, anemia, hormonal imbalance are a few of the other causes. also as your periods are late by just 4 days, i suggest an ultrasound to diagnose pregnancy. I would recommend a repeat Urine pregnancy test after 10 days of your expected date of periods if it comes negative now. If it is positive or there is definite signs of pregnancy on ultrasound, consult your gynecologist for prescription of medicines to terminate pregnancy. These drugs are not available without a prescription, so you will need a written prescription by your doctor. Hope this answers your question. Thank you.