little help

Monee
My period is never late unless I'm pregnant. I have (3kids).. so my last period was march 14 and it's only a two day thing (normal for me ) it's now may and still nothing.. took 2 pregnant test one home n one at Obgyn on Friday both said negative.. could I be pregnant and it's not being detected yet or do y'all think it might be something else... did blood work n waiting for that to come back.. but in the mean time just look for maybe some help