LavendarRott offers good advice.
Taking the pup to the spot to have a talk isn't going to change anything either. In order to make your message clear you have to catch them in the act or there is no association to the deed. You can be firm yet gentle in your correction in order to claim your territory, but try not to scare her just impress her that the house is your territory and not hers to soil, but outside gets all the good stuff (as you are already doing). I do agree you are teaching her to go inside and out so the message isn't clear.
If she is acting like a puppy then you must teach and continue to manage her like a puppy. She gets the freedom and your trust as she earns it.
Love Them & Lead Them,
~Elizabeth & Doug
Dog Training the Way Nature Intended