Blood in my stool. dark red like period blood on the toilet paper but in the toilet it looked pinkish red. i've had diarrhea for 3days no blood til now?

Hard to say: I suspect you have a problem that may resolve on its own. You may have rectal bleeding due to the diarrhea; you may have ruptured a hemorrhoid . If the bleeding continues, you should see a physician. Primary care doctors could do a small scope procedure to examine the inside of your rectum to help diagnose the problem. You could have an anal fissure that is bleeding. See doc! Good luck!

Get an exam: These symptoms could be due to a intestinal infection which may require treatment or to an inflammatory disease of the colon. You really need to be checked by an appropriate doctor - either a Family Practitioner, Internist or Gastroenterologist.