Tortoise age???

[Redfoot!!!]

Hello everyone, my name is Alshad and I got my redfoot tortoise around 1 year and 6 months ago. At the time I got her she was around 11-13 cm (Around 4-5 inches) long. Now she is 18 cm (Around 7 inches) in length. I want to know her age, so if anyone here could tell me out of the given information it would really help me a lot. Thank you!

 

[ZEROPILOT]

Probably close to 3 or 3 1/2 years old.
But I can't tell you the birthday.

 

[Redfoot!!!]

Probably close to 3 or 3 1/2 years old.
But I can't tell you the birthday.

Wow, ok! Thanks for your help!

 

[Redfoot!!!]

Hi again, I just weighed her, and she is 1278 grams. Is that ok for a tortoise her size or am I overfeeding/underfeeding her? I also forgot to mention that she is 13 cm (5 inches) in width. Thank you.