There has to be something after "I know" otherwise it just sounds like "get lost".
Nah sorry, you misunderstood and have primed yourself to assume the worst. It was a joke as Taril said, as in she doesnt want to make it too serious and cheesy even though she likes the compliment, it breaks through awkwardness. Or you can see it as teasing and being playful, which is appropriate in flirting stage of relationship.
It's similar to this from Star Wars:
Also modding - this is just you making up your own headcanon to cope rather than truly engaging with the material. You should be more secure dealing with female characters and be playful back at them. Such modding is a lie.
