Pregnant or not???

I am so incredibly frustrated with not knowing if i'm pregnant or not! The days seem to draaaaag. I'm 5 days late, took 3 home tests, all say negative but still no period. (Before this) I'm not stressed, nothing in my life has changed, everything is actually going wonderful can't think of a single reason why i would be this late! I'm kind of cramping but not as severe as usual, i've had lower back pain for the last 3 days, extrememly exhausted (even with plenty of sleep), um (hope this isn't TMI) but i've been constipated the past 2 days (i can't remember a time when i EVER have been...so kinda weird...) I took a blood test yesterday and i have to wait a couple days til the results so im getting antsy....any opinions or advice? Thanks :)