Hello stinky94louise94 welcome to HCM,
You have undergone two major abdominal surgeries which should be worrying you rather than not pooping for seven days as after most of the abdominal surgeries patient wont be given anything through mouth, so no input obviously no output.
First you have undergone appendicectomy after that you might have developed haemoperitoneum which means collection of blood in your abdominal cavity which might had been due to any reason, thats why you had reccurent fainting
and blackouts and also vomitting everything that are taken through mouth and after that they might have performed surgery for that and transfused blood to compensate for the blood loss. Its a dictim that patients wont be given anything through mouth after major abdominal surgeries thats why you are not passing stools. The problems to worry for you now is about your improvement in general condition after second surgery, what caused the bleed inside the abdomen after first surgery and the success of second surgery.
Hope for your quick recovery, Dr. Parthipan