Potty train derailed or on track?

Well I have no idea what I am doing or what to do. Don't tell my husband though, or I will deny it! We have been working on potty training. I haven't pushed the issue because I didn't think she was ready. Lately I am not so sure. The past couple days she has undressed herself for a bath. Then today after dinner she was filthy. She was wearing most of her dinner. So I took off her clothes and let her play in her diaper. Big mistake. She came into the dinning room naked. She looked at me and said, "Poop!" While she pointed toward the toy room.

I thought, "Oh, Crap!" Literally. I walked to her and saw her diaper on the floor a few feet from her. I slowly walked down the hall as if I might find a ghost or some monster. As I carefully searched the floor I saw it. A big pile of tiny turds! At least it wasn't on any toys and if wasn't to squishy! You know the kind I'm talking about. I used the diaper to pick it up and toss it. Then I washed the spot on the floor and all was well.

I asked her, "Why didn't you put the poop in the potty?" She knows poop and pee goes in the potty, but I didn't get any response other than a stare. As if she were saying, "I'm not telling!" I'm not sure if she knew she had to go and just wanted to go there. Maybe she was busy playing. I don't know. I do know that it is time to start the potty training. But where, how.

She will sit on the potty chair with clothes, but naked not so much. One problem is that her brother constantly tries to climb on her. Giving her little privacy unless we are in the, but she doesn't want to sit in the bathroom. I have heard of giving toys every time they go, but if you start that where does it end? I also don't want to rush her or force it, but if she is ready I want to guide her the right way.