Hello, I Am A 47 Year Old African American Male,

Hello, I am a 47 year old African American male, and last week after band practice I noticed a good bit of blood in my underwear. I immediately went to the bathroom and wiped because I've had issues with hemorrhoids in the past, but there was no blood when I wiped. I also urinated and found no traces of blood at all in my urine. I check myself the best that I could, and I couldn't locate any cuts either. What could this be?