I have a 13 year old rat terrier. She has diabetes. She is on insulin but for the past several months she pees all over the house, even five minutes after she has gone out.. Help.. not sure what 1 should do

I would say that this little dog should be taken back to the vet. Sounds like she needs her insulin increased. Hope she's well soon.

I agree it sounds that her diabetes is not being controlled and her insulin needs adjusting.