There Will Be Blood - Am I an idiot for thinking that Paul and Eli were the same person for most of the movie?

I watched There Will Be Blood for the first time the other day and I feel dumb.At the start Paul comes to Daniel and tells him about the oil.Then he goes to the farm and there we see a person who looks just like Paul and valls himself Eli. Paul isn’t mentioned.He gives him an handshake and a knowing look that felt to me like "we met before, but don’t blow my cover".I assumed Eli went to him to tell him about the oil to expand the church, but he used a fake name at first to be safe.So later when Daniel low balls them and Eli speaks about the oil, I thought it made sense since he’s the reason Daniel came.Only much later in movie when Eli yells at the family about Paul I realized he was not Paul.I thought that I must be terrible at faces, so I checked IMDB and no, they were both played by Paul Dano and are supposed to be twins.So, am I a complete idiot? Did anyone else have the same experience? Did I miss a line or something that explains it? via /r/movies https://ift.tt/IvlNtZW