Yes. No.

now that's interesting, possibly that's what killed mine! I was a bit secateur-happy!

It is a herbaceous perennial flowering August onwards. Cutting down any stems now would do nothing much for the plant, All we ever do with the dozen or so we have is remove the dead flowering stems in late Winter. If there is only one stem growing then give it a feed with a general fertiliser, it should soon bush out.

thanks very much owdboggy and weeding