She’s a golden/shep mix. She’s fixed. She doesn’t have worms. I keep catching her rubbing her butt and I’ve been finding skid marks on my carpet! Please help!

My apartment frequently experiences little black worms that curl up in a sort of half-moon circle when touched. They show up on my carpet and patio. Can you tell me what they are and how to get rid of them?

I’m watching my sons dog today and found out that the dog has tape worms so I am concerned about my other dog that lays in the same area.
do I have to disinfect carpet and bedding? If so what is the best method?