I want to add the included link below have helpful keys details i.e. flowers & leaf shapes of other species and genera in the family for you to compare to the West Indian Woodnettle. Click on images to enlarge. Hope it helps you further in narrowing it down.
To my eyes the flowers are looking similar the L. aestuans? According the link, its male (staminate) and female (pistillate) are on the same panicle while L. canadensis ” the upper are female, lower male”. Best wishes!

http://www.namethatplant.net/gallery_compare.shtml?compare=False%20Nettle,%20Wood%20Nettle%20and%20Stinging%20Nettle

Thank you for these great photos with nice, clear view details of the plant. Since it had self sown in a tropical plant pot, the Peace lily, maybe a tropical species in the Laportea genus (? ), possible the West Indian Woodnettle (P. aestuans)? Check it out and see if you have a match.
Again not having the plant in person, I could only speculate. Click on the image in the included link below twice for macro view of flowers & leaves details. Best wishes!

https://en.wikipedia.org/wiki/Laportea_aestuans

Check out images of West Indian Woodnettle photo gallery in the included link below. Click on the icon in the lower right hand corner to enlarge the images.

https://florida.plantatlas.usf.edu/Plant.aspx?id=1681&display=photos