Doctor, I Would Like To Know If I'm Pregnant. I

Doctor, I would like to know if I'm pregnant. I had sex on the 1st week of December 2015 and then had periods on the last week of that month. Again I had periods on the last week of January 2016. But I missed my period of February and now it is the last week of March. I don't know if I'll have my period this month. I have no major symptoms of pregnancy such as nausea, headache. I'm really understanding if my breasts are swollen. I didn't do any pregnancy test. And I'm only 16 years old and afraid from confessing about it to my mother. Please tell me what's your opinion about it.