I’m not sure if this is an indicator for Candida, it can happen for different reason. However, I would assume you are more likely to have it if you have Candida, since I actually had the same problem after the first time I introduced Kefir to my diet recently.
However, the problem was not new to me I had this already 1-2x years ago from certain foods and went to the Hospital as I was worried. I was told that the importancy is to check if the blood in your stool is old or fresh. Fresh blood will obviously be brighter colourful and come from your intestine and is not -normally- (!) not dangerous. If the blood in your stool is old, i.e. more dark red then the bleeding occured not in your intestine but in your stomach and you need see a doctor asap. I would see a doctor in any case should the bleeding occur more than once in short period of time.
Hope that helps.