Calm down. Relax. It isn't over yet. Mid-October is going to be fine, but you do need to study and rock it when the time comes. I recommend that you relax and do nothing in regards to the DAT at least for a few days. Take a break!
Like I said it isn't too late. Who knows what could happen? Just study knowing that you need to do well in October. Going crazy and posting frantic threads on SDN isn't going to help! 🙂