The photos are a bit blurred, Marleenjongen, but it could be a Veronica longifolia or a Salvia, possibly.

looks a bit like a stachys as it also has soft hairy leaves. Mine grow tall like this too.

I have one as well, and like you I don't know what it is. It could be one of the Salvias because of the scent the leaves have, and the flowers are like it.

Finally, a friend of mine who is Portugese and into gardening came by and I remembered to ask him what this plant is. In Portugese: Boldo-de-jardim. Its proper name is Plectranthus barbatus. It has many medicinal uses, if you are into natural medicine. Hope that helps.