When am I going to start my period?

I'm 12 years old, and I need to be prepared. All I have is panty liners for my discharge. (I've had discharge for over 1 year.) I have every sign and I think I'm going to start. I kinda want to, kinda don't. I'm home-schooled so I don't have anyone to impress. I have pubic hair. (2 years) I've been having cramps. I've been really moody lately, and I've been having bad headaches. (I drink A LOT of water and been taking Ibuprofen.) I've gotten one yeast infection because of my discharge. (I think it was my discharge.) I'm stressed out and depressed. (Mostly because of my anxiety.) I've also been mean for NO reason. I always end up begging my parents for my favorite foods. (Like nutella, cheesecake, and sushi.) And my neck and back hurts all the time. (Most likely from my stress.) I'm tired all the time. I've been bloating, too. I'm scared, and this is what is stressing me out. My mom started when she was 14, and my sister started when she was my age. So I don't know if I'm going to start right now or at 14. (Sorry for all of that information, I need to know since my mother isn't sure.)