I have not had a period since Dec. 05. I'm 26 years old I have Grave's dis. but I wanted to know if anyone knows if there is an age for menopause. Please help

Have you seen a doctor and talked to them about this? One of the sign/symptoms of Graves disease is having a lighter menustral flow. Are you taking any medications for your Graves because that could also maybe alter your cycles. I would recommend you see a doctor about this. Let us know how it turns out.