Kitten, litter box, behavior?

We got a kitten about a month ago. She's barley two months old. When we first brought her home we put her in the litter box and moved her paw and bam she starting using it. Then today I went into the bathroom to find a piece of feces on the carpet. (her litter box is another room) So I cleaned it up and start cleaning the home. When I went back into the bathroom about a half hour later I found another piece. I now have the bathroom door closed. But I was wondering if anyone could tell me why she is doing this. Her litter box is clean with fresh litter. I haven't changed anything about her box or spot from the first day. She is not sick or ill. Nothing has changed in our household to cause anxiety. Please someone give me advice.