Talk to your schools nurse.
There's certainly nothing to be ashamed of, so even if you're not close with your mom, you should be able to talk to her about it. The suggestion that you speark with your school nurse is also a good one - she probably has materials available that she can give you to answer questions you probably have. This may be too personal to talk to friends about, but if you have a really close friend, talk to her about it. She may not have answers, but may be able to offer moral support. Check your school and town library - look for Our Bodies Ourselves, a great book for teens. It has has several printings and editions. If it does not help (but I'm sure it would), there would be books of its ilk that should appeal to you. You can get through it - every woman has to. You may just need a little help and advice to get through it a bit more easily. Don't be afraid to ask!
I cant go to the nurse unles im sick,and my teachers dont bye my sick acts and i dont want to tell me teacher.if i tell my mom she will get all gushy.and plus i had a phsical yesterday and i lied and said i havnt had "it" yet.im getting buy oin my moms suplys
Well just leave her a note to buy you some tampax.
i am probably your age too, so i know how you feel.I think you should tell her strait out!shes your mom! or,do what the other person said, tell a friend! ^_^