What Causes A Delayed Period,stomach Cramps And Tender Breasts?

Hello, Im 27 yrs old, my boyfriend and I have unprotected sex all the time & for the past month he has been ejaculating inside me. It's been 42 days since the day of my last period. I've taken 3 hpt And they've come back neg. I'm crampy all the time, moody, gasey, breasts are very heavy n tender & nipples very sore n tender. Is it time to see a doc?