Can lower stomach pain and lower back pain be a sign of pregnancy still 1 week to go before af due?

Yes could be. I had this signs a week before my period. But I knew i was pregnant even if the test was negative. My husband and I are trying to conceive for 2 years with our second child. So after 3 days of missed period i checked again and true enough i was pregnant. I also had spotting (Brown-red light discharge). Goodluck!