Hi lisafoster. Welcome to the forum.

Blood in the stool is what is called a "red flag" symptom - one that must always be reported to your doctor. So your next step is to phone your GP at 8am tomorrow morning and get the next available appointment.

However, despite Google, blood in the stool does not automatically mean cancer. Sometimes it can come from swollen piles (varicose veins around the anus), particularly if you've been straining hard or wiping too enthusiastically.  Sometimes it can come from a harmlessly ruptured vein inside the bowel.  But it does need to be checked and for that you need your GP.