well as you probably know, stress can cause changes in your cycle that normally would not happen.

The other thing I thought about was perhaps you do not have a normal luteal phase of 14 days. If you thought you did, but did not that would also explain why it seemed AF came early. Are you just now starting to chart or have you been watching and charting for a while? If you have been watching for a while, is your normal luteal phase 14 days (assuming you have been able to pin down the date of ovulation normally)?