What's wrong with her? :(

just bought her and a male today, unsure of age but they are both full grown. she keeps getting stuck upside down, can't seem to stand on her own. she also keeps rearing her head up and falling backwards. I don't know what's wrong with her, I don't want her to die on me already :(

she's also making this chittering noise as heard in the video. maybe she's just frisky cuz she's with a male, but idk about the falling over when just walking. anyone else know??