My dog defecate in her bed

Question
Hi! I have 5 year old shi-tzu. It is girl and her name is MJ.First time it happened a month ago.She peed in her bed.Two weeks ago she pooped in her bad again and she stayed there. Today I put new clean pillow in her bed and awoke up at 5 a.m. from smell.Shee peed and pooped in her bed and was laying there in all this.There is no changes in our life but i have noticed that she has her period now.Could there be connection? But it 's never happened before!And when I have punished her and took away her bed, she was sleeping on the carpet in my bedroom and there was no accidents.

Answer
Take the dog to a veterinarian ASAP.  She may have developed a uterine problem.  Dogs need to be spayed and neutered at young ages in order to prevent all sorts of serious health problems that develop because of hormones.  She may also be marking her "nest" as a result of a false pregnancy or a hormonal problem.  If she has no physical abnormalities that the Veterinarian can find, allow her to resolve this heat cycle (six to eight weeks) and HAVE HER SPAYED.