Ok first off I congrat you on wanting to get on birthcontrol. You don't necessarily have to tell your mother. You can go to family planning and at that young of age you can probably get it for free. Everything is confidental at the family planning center. Or you can tell your mother and at the age of 13 she can freak out on you or she might take it as you being very responsible. Trying to get out in the open is fine. It is good that you are getting on birthcontrol or even thinking about it. But remember getting on birthcontrol does not protect you from other things such as std's. So good luck and remember be safe. And I hope for the best and keep me posted thanks.