don't worry about what she said, think about how dd interacts with you. if you ask her to get her shoes/ pick up her toy, does she understand you?
why was she referred in the first place? this will give you some clues - is her speech delayed/ unintelligible or completely absent?
if you say 'milk or juice'? does she understand and make a choice (whether verbally or otherwise?)
at home, if you use her name does she understand that it refers to her? does she understand that you are 'mummy'? - if you play peekaboo, or hide and seek, and say 'where's x/ mummy' does she know if you are looking for her, or if she needs to look for you?
what are your concerns about her speech or understanding?
is she usually shy with strangers? sometimes an assessment is affected by the context (complete stranger saying 'x, where's the puppy?'), whereas if you asked her the same thing at home, she might be able to tell you. (sometimes it works the other way too - dd2 had an ep assessment and was answering questions i had literally no idea she would be able to)
try not to worry - the fact that she is in the system at such a young age is really very good news, and the slt is obviously keen to follw up, so think through what you want to ask at your next appointment, and write it down, so that you don't forget.
difficult to say what she's getting at, but you know what worries you have.