What Causes Headache, Swollen Belly, Weight Gain And Breast Tenderness?

Hey it is related to the gynecologist.. Last month my periods starts from 27 of july and it were very light and continues 20 days as on 13 august and were enough light that i even did not consume a one pad whole day. on 14 of august my husband and i did an unprotected sex and he gave me a medicine which i took but my periods cant come and after he gave me anothr medicine name gynasicod today..i am feeling abdominal pain nd a bit headache and swelled belly,weight gain and a bit pain in my breast..whether i am pregrant or not