Everything is fine. You have been seeing the urates, not poo. Their poo does resemble a dog turd. They are usually a lot less frequent than the urates. If you weigh your snake frequently, you can be quite suprised how much a turd can weigh.
How long have you had her?
I haven't had my snake very long, but it has had multiple poos but I have never seen a urate. Is that normal?