Is this any type of possible like i didnt know i was pregnant? please read! thank you!?

in july i had some light bleeding and decided to take a hpt which i did it was a bfp within seconds a few weeks later got a negative blood and urine test and a normal like period since that incindent ive been having all types of weird symptoms always tired, nauseous, hungary, peeing like crazy and my got slightly bigger, and my stomach even gotten bigger i been to the docter several times since and negative blood and urine test :( its so crazy ive been having which seems like my monthly periods since then but they always seem to come a few days late or sometimes a week or more late ive been having these real bad stomach cramps that the docters cant seem to figure out why iam having them and my been producing colostrum for months now the docters never figured that out either i know its not a hormonal imbalance but whats going on?? like has this ever happened to someone and they where infact pregnant and never knew it like on that tv show i didnt know i was pregnant?