Is my guniea pig prehistoric?

i have had my guinea pig since june 2005 and they said she was almost 5 months old. is this old?

Answers:
She is approximetly only 2--that is young--BUT to breed her, at this age is NOT recomended that you breed her, because her pelvic bones own fused

I got a male who was approx. 4 months behind the times in 2004. He is still alive at age 4 years old