I have had mine, so I can offer a little advice.
1 - It hurts A LOT for me, I get really bad cramps, but it didn't for my first couple times. If it hurts for you, I reccoment painkillers and/or a hot water bottle/heated stuffed animal. Also, tea helps, I love tea. It can be sweet or unsweet. Lying in the fetal position or just curled up in a ball can help too.
2 - start with pads. Tampons can be pretty confusing/ scary the first time, and I personally have never used one. Wait 'till you're older.
3 - calm down. Stress can make the pain worse, and though it is a little scary the first time, you get used to it and it really becomes just more of an inconvenience. When you get it, just muster all your courage and tell a trusted adult that you got it. If you're at school, just tell your teacher that you need a cough drop, and go ask your school nurse. Change your pad every 2-5 hours, or whenever you feel like you need to.