If you have a period of time at night or during the day of 5 or more hours of not nursing then it can be that you'll get your period back, to up your supply and maybe stop you period try, nursing and offering more, pumping on the other breast whilst baby is nursing, pump after baby has nursed on that breast or pump inbetween nursing just make sure it's around 1hour after the end of the last nursing session. You can also take fenugrec tea - dates back to the egytian times for augmenting milk supply!
You could also visit the threads where mothers have supply issues which may be helpful - but you know sometimes although you are not ready for this, it may jsut be one of those things - hugs to you.