You’re not alone in this remembering every plant. Just yesterday I was bringing a pot inside before the coming freeze and set it next to the pot of Oregano. I stood back and looked at both plants and thought, “what is this plant?” It looked very similar to the Oregano. LOL I started thinking is this a different variety, etc? Finally, I did the sniff/taste test. Sure enough, the O had much stronger smell and taste, and was distinctly different from the other plant. I decided the new addition is Thyme because it was more earthy and sweet.
Sorry for rambling on but I do find plants, especially culinary/medicinal, very interesting.