Should a Shaken Espresso be completely mixed or is it supposed to be layered?

Iced Hazelnut Oat milk Shaken Espresso

I changed 4 shots to 2 and Signature instead of blonde

I don't drink a lot of coffee, nor do I regularly frequent Starbucks. I typically order an Iced Latte and all the ingredients are mixed. I've ordered the "shaken" espresso twice now and it looks like it's got Pepsi in the bottom? Is this norma, is that the hazelnut? Am I supposed just drink and it mixes as you drink? Is the "Shaken" referring to something else? Should I just go back to Latte?

Sorry if this is Starbucks 101, but appreciate the help.