Hello there!
She does appear to be a Serama. Technically, there are very few specific Serama breed requirements, aside from being very small.
The "purpose" of a serama is to be shown, while posing on a table. These poses, as I am sure you have seen, are extreme. They pop their chest out, tail up and head back. THIS is what Serama breeders have focused on for quite some time. Like other chickens, an attractive appearance is desirable, but unlike them, feather color, patterns, etc are irrelevant. Serious breeders just want them to pose on the table, behave themselves and crow on command. As a result, Seramas have generally turned to a "mutt" breed - with some folks still following some classifications or naming them after their color.
So, what you have here would technically just be called an "American Serama"