Alexis is right. Stress could very well be a huge factor, and it will change your cycle patterns. Even with the most regular people. Stress affects the body in so many ways. It is important to try and relax. I'm going through the same thing. I started a week early this month. I had my regular cycle at the beginning of this month, and then on the 20th, I went to the bathroom, and twice there was blood. Kind of scary, but just thought it could be my cycle changing its course. And sure enough...here I am a week early. My husband and I are trying to have another baby, but my system is not. LOL And like Alexis said, the stress with wanting another child, and no luck at the moment, is quite enough to make your body change its course. You and I both just need to relax and let it happen instead of worrying ourselves about it. :-) Glad I'm not the only one here. LOL
Take care M., and I wish you the best.