When I was wiping, I have found blood on my toliet paper. Help, please.?

Possibly hemmies or a minor anal tear if you were constipated or if the dump felt painful. Could also be anything from an ulcer to colon cancer. Make an appointment with the doc if it the dump was normal, otherwise take some fiber so you don't irritate the less severe possible causes.

Perhaps you wiped to hard or vigorously, and you accidently scraped your skin.
Wait a day, and if the bleeding doesn't cease, go to a doctor.