Diarrhea and urinating that feels like acid.... also blood coming out of anus. haven't been sexually active in four years. need help?

Go to ER: You should get evaluated immediately if there is gross blood or bright red blood coming out of the anus, you may also a have a urinary tract or bladder infection if there is burning or acid feeling with urination.

Seek medical help: Rectal bleeding could be from external or internal hemorrhoids especially if blood is bright red. But there is no way to correctly diagnose online. Please see a doctor as soon as possible for prompt diagnoses, treatment and reassurance. Good luck.