dog housebreaking

Question
Hello, I seem to be having a problem with keeping my dog from going inside. I take her out and she'll relieve herself there. We'll wait a bit, then she goes up to the door and I let her in. Now, the problem is sometimes she'll go into the kitchen and do it again, sometimes within 20 minutes after coming back in! Why would she defecate outside, then do it again inside? After she does it, she'll put her tail between her legs and hang her head and hide behind the couch. It's not diarrhea, like she had before, I couldn't punish her for that. Vet gave her a clean bill of health and I see no abnormalities as far as my laymans eyes can see. Any suggestions would be greatly appreciated.
Also, I rarely catch her in the act itself, so it seems my window of oppurtunity to chastse her and put her outside is usually missed.

Answer
First of all, you cant let the dog out to go potty. You need to go with her and when she does it get excited and tell her good potty. next, i have a puppy that goes twice in a row within a half hour, it all depends on the dog.But since i know this, i take her out, praise her bring her back in and put her in a crate for about 20 more minutes and take her back out. once she goes the second time, i know i am safe for a while. It is up to YOU to teach the do where to go. It is like potty training a child. Try this for a while and see what happens. Good luck
nancy