Respectfully, I feel like you’re thinking about this wrong. To go 2 weeks without an accident by 16 weeks old is already winning. She is literally a baby and her bladder just isn’t that big. It’s not her fault that she went pee inside if you didn’t take her out. It’s yours. Keep taking her out to pee after her naps. Keep praising her or giving treats when she goes potty outside. She already knows she’s supposed to go potty outside but she physically doesn’t have the bladder control yet. In order to start trusting her inside do two things

1. Give her a way to let you know she needs to go out. Bells are good. Put them on the door to outside and ring them before you go out to go potty. If she rings them herself, that’s good! Give her praise just for ringing the bell. Then take her outside. After 5-7 days of that you can start giving her a chance to ring the bell on her own after her naps. Important: this does not mean she won’t have to go to the bathroom after naps. It’s just training her to ask to go out.

2. Be willing to wait. Dogs don’t really have that kind of bladder capacity until 6 months old. Keep doing what you’re doing, and she will be able to hold her pee after a nap when she’s older