Period 17 days late, could I be pregnant?

Patient: Hello. My last period started February 13th, 2015 and lasted the normal five days. My cycle is usually 30 days and very regular. I have taken many hpts and have all come back negative. I went to the doctors when I was 9 days late and had a urine test done and it was also negative. I haven’t been on any form of birth control in over a year. My period is now 17 days late and I’ve had some symptoms like back pain, fatigue, nipple and breast soreness, nausea, slight cramping and dizziness. My mother didn’t know she was pregnant until she was four months along, both times. Could I still be pregnant?

Symptoms: Back pain, fatigue, nipple and breast soreness, nausea, slight cramping and dizzines

Doctor: