dead nettle is a tall plant though like stinging nettle, this looks like a ground cover plant - not that I've been able to open the link after the first time.
Mrs Hymie has green fingers but I have developed a foolproof method of identifying weeds.
When attempting to pull the plant out of the ground – if it comes out easily (roots and all) it is not a weed, but a valuable plant. As a general rule, the easier it can be pulled out of the ground, the more expensive the plant.
Whereas, if no matter how hard you tug at the plant, it remains steadfast in the soil – it is a weed.