This is my 2 cents about the dog issue......
Get a crate that is sized correctly for her. It does not matter that she wasn’t previously crate-trained, she needs to learn the rules. She may make a stink about it, but don’t give in
She needs to go in the crate whenever you are not in the house or are unable to keep an eye on her. Don’t use the crate as a punishment however, only as a means to contain/control her when you aren’t around. Make her sleep in the crate at night too.
Next step is get her on a schedule. If she’s used to free-feeding, stop. Offer her a measured portion twice a day. What she doesn’t eat within 10 minutes, pick up.
She needs regular, supervised potty breaks. If she’s easily distracted, keep her on leash until she’s done her business. Set a timer to remind you to take her out if you need to.
If you find a poop or pee in the house, don’t shove her face in it or punish her, she won’t understand why you are doing that. Verbally correct her only if you catch her in the act. We use a sharp “eh” or “oi” as our displeased tone and usually, if someone is being bad, as soon as we make that sound, they change their behavior. Even my 17 week old puppy has that figured out.
If you catch her in the act, quickly move her outside to finish.
Small dogs can be brats about house rules/house training, but if you are firm (not harsh) and consistent, they can be trained.