I actually reckon it’s more in-character for her to yell out for Peter. Her feelings for Nebula are so, so complicated, but she did hate her, like she says at the beginning, not so long ago. Whereas Peter, whether she loves him romantically or not, he’s very dear to her and his death would absolutely shatter her.
But the way she does look at Nebula when she lands, I kinda of read as her thinking something like “This is the most terrible thing I can think of, but I am glad you’re alive.”
