potty trained??????

Ok, I know you see the question marks, so let me tell you why they are there!

Kenzie has gone almost a full week with no diapers during the day! She is so super about going potty and we are so very proud of her accomplishment.
The problem is if she has underpants on she has accidents. She will realize that she is peeing and run but when she gets to the potty she is not only upset she is wet and so is my house. To be honest it may sound gross but I am more worried about her then the house.
My question is why? We have been putting her in pull ups forever it seems like but even the cool sensation ones have no effect on her. It seems to me that pull ups are to close to a diaper maybe, but underwear? Could it be that she forgets when she is dressed that she does not have a diaper on being that she was use to having one. So we let her run around the house naked from the waist down (she has been living in sundresses and nightgowns), and a few times a day I do put underwear on her but that is when the accidents happen.
WHAT DO I DO???? Any comment is helpful please guide me I am lost!