Does Vaginal Discharge And Nipple/back/stomach Pain Indicate Pregnancy?

Hi, I had sex ( with condoms) with my fiancee on my 14th and 15th day (i.e. May 7th and 8th). I took and Ipill on May 8th night. My period is due on May 20th, but still I have not got it. Sometimes i see all the symptoms that of pregnancy. I have not yet taken the test. Could I be pregnant? I am having bad nipple pain, lower back pain and even stomach pain and I am having more vaginal discharge too... I feel like all these symptoms are similar to pregnancy symptoms... SO I am very frightened..