it could also be something she ate...check her poo today and see if there are still mucus. I see mucus from time to time hee but not quite like what you showed...more stringy..I watch to see if it clears up..check worm issues and so forth..usually clears up on its own...sometimes worms were the problem..
could be she ate something that is working its way through the system...if she is doing well other wise, has a good temp, eating drinking pooping berries ect...I would keep an eye on her the next few days but not worry too much unless things change for her..
Also worms shed eggs in cycles...so I would recheck her poop in 3-5 days..see if anything changes...could be her fecal sample was between cycles..
Check her for anemia as well..