Yes, this teal did look a bit different. I think Judy is correct that this bird is still transitioning into standard male plumage. The white vertical bar and the green in the secondaries can be hidden at times. I would need to see additional photos to compare. Bill looks normal to me.
Have a look at these other photos on Flickr as there are a number of birds that look similar.
https://www.flickr.com/search/?text=fal ... ged%20teal
Upon review, I did consider an Intersex bird but don't think this is the case. This bird has mostly male patterning. Not an expert on intersex birds so don't really know what this could look like. Not a lot of detail on the web.
I don't think it is a Green winged teal x hybrid as I am not seeing any patterning that suggests parts of another duck sp.