Thank You. I Have A Tea Cup Poodle Age 10

Thank you. I have a tea cup poodle age 10 weeks .She has hd a problem passing stool for about 10 days after a vaccination for Parvo virus. She is alert and eating OK. She was raised on chicken necks(ground). Has a small bowel movement every 2or 3 days but always straining. I worry about prolapse of her rectum. The breader says she has seen this go on for 2-3 weeks. No blood or mucus in the stool and no evidence of tape or round worms. Help