Q. My 28 lb 10 year old Maltese/Boxer mix has had blood in and around her stool for 48 hours, I took her to the vet 10 days ago because she was limping
A. We should get more information in order to be able do advise you, in general we can say that blood in feaces is from the last tract of the intestines and can be secondary to an acute infection or a more chronic problem ( colitis).
I would suggest that you have your dog checked over. If it's a small mount of blood and the dog is still eating normally you can wait until your vet is open. If your dog is having diarrhoea with blood or if he is not eating, or is in pain, you should have him checked over today.