Are Delayed Periods, Nausea And Enlarged Breasts Signs Of Pregnancy?

It has been three days since I missed my period (February 28) . I had unprotected sex 2 weeks ago on the 15th of February ( used withdrawal method). I have been getting symptoms like enlarged breasts , nausea , bloating , gas and lost of interest in sex for the past week. Am I pregnant and should I take a test ?