Get to the doctor asap! They will give you a ton of resources on the best diet, exercise, etc etc etc. No matter what - it is always best to get checked out as soon as you know. And, then they will be able to accurately peg the anticipated due date.
You are entering a very very exciting time of life! And every pregnancy is different so what you may hear from some people may or may not happen to you so above all don't worry! This is a great time in your life so relax, enjoy the changes (instead of crying over them) and exhault in the fact that you are busy growing a new life, girl!!!! What an amazing thing that is!
There are a ton of great websites out there as well for expecting mothers. Mom.com is a good one to start with. They have charts for keeping track of the babies progress and lots of info on what to expect, changes that will take place, etc.
It is a very good idea to check some of them out - you get a lot of support through the other "new" Moms and much needed information without the horror stories!

But...first step - go to the doctor! *said with best "mom" stern-voice!
