pain above rectum ?

HI there i've had pain above the rectum it could be from there i don't know or it is on top of it it hurts when I sit or stand up too quick. i've had surgery when i was a baby i was born with no rectum and they had to put it in me my fiance noticed that my butt been sewen together? i was also wondering if that could be unsewen where i would have  a normal butt and the pain i was wondering can something be going on with the rectum they put in? cause it feels like a pull when i am in pain it hard to exlain like it feels like something ripping open. any help will be great