I'm 17 DPO and 4 days late today and taken 2 pregnancy tests and both negative. Took one the day I was due and one this morning. I NEVER miss my period and it is NEVER late. My husband and I have been trying for a few months now so the fact that my period didnt show up was exciting for us. I'm having light cramping and my nipples are so dang sensitive. I cant explain what this would be but pregnancy tests are negative. Should I go to the doctor for a blood test?