It could be. It could also mean you have a cut near your anus and the blood mixed in when you were going to the bathroom. Constipation causes cuts if your BM was rather large. It could also be you ate something that caused it. Keep an eye on it and if it continues you need to go to the doctor to make sure there's nothing more serious going on.
IT CAN BE AN ULCER. YOU WILL NEED A COLONOSCOPY TO BE SURE. THEY HAVE A SMEAR TEST YOU MUST DO FIRST. GOOD LUCK, J3211