Please advise

I am 10 months trying for baby no 2, as of today my period is 3 days late today is day 29. Of my last 12 cycles only one went to 30 days. I have been experiencing a lot of lower abdominal cramps for the last 3 days and tender breasts, should I wait another few days to do a pregnancy test I'm not sure if I could face a neg or should I just do one and get it over with, can't stop my period from coming I suppose...