Hello, I Have Been Having This Problem For So Long,

Hello,
I have been having this problem for so long, my problem is that I dont go to the bathroom as much as I eat.. I eat alot but I dont get it out of my body. Sometimes i have constipation and if I go to the bathroom it diarrhea but its not much... so little gets out of my body and i dont know why.
I eat lots of carbs lots of chocolate some soft drinks ... i dont eat outside. Also recently i have this pain that comes and goes in my lower right abdominal its constant comes and goes and dont know why!.
I dont eat alot of vegetables nor fruits ...
I am almost always stressed
Sorry for making this long and thank you