I need help right now. My horse is starting to colic.?

Okay, yesterday morning my 4 year old mare got to much hay and she was laying down. She wont eat or drink right now. We have punch in her water bowl, a little bit of salt, and some bran to try to get her stomach moving. We called the vet and he said he would come out if it gets any worse. She has been on the walker several times since yesterday morning. She has been using the bathroom, but not like she should be. Please give me some answers quick.