/lit/ - Literature

I could use a bit of advice, /wg
See, I've painted myself into something of a corner. My piece is set around the 850 a.d. and has a comparably level of technological development, though I have made some exceptions.
However, it has occurred to me like a slap in the face that I have described several character as using plate armor. Naturally this is somewhat anachronistic, and since weapon development is always chasing armor improvements, giving the world the metallurgy responsible for plate armor would throw a rather large monkey wrench into the world's future, since who is to say what full plate could possibly evolve into given 300 years and no gunpowder/cannons to counter it.

Am I overthinking it? Is this something which only I will notice? Or should I simply go back and redesign these characters armors?