She left a message for her younger self to read. -- SongSpired
Time travel was a bitch. Sorting out the mistakes of life retroactively was never a fun thing. Making sure she would pay attention to her own warnings to herself had been the work of several journeys. And multiple encounters. She could not talk to herself. Both brains shut down for that sort of thing. Leaving notes, however, was perfect.
Her teenaged self was asleep in bed. Sleeping the sleep of the unaware.
She put her note in the jewelry box, where she had always left it. She had always had the only key. And then she left. Back to her own time and to the decompression suite where she would wait in isolation for time and her memories to resynchronise.