Indeed, it seems she has taken it the wrong way. (Or, perhaps, the wrong way was taken by you.)
She felt she should explain her motives for sending suggestive photos and borderline-flirty quips. Maybe you have concluded as much, and maybe she even told you already, but it's been an uncomfortably long while since she's let herself feel any sort of emotion toward people...in general. She's been drifting along, in different parts of the world, for almost four years, meeting a million people, but connecting with a rare few. Sadly (or not, depending on personal perspective), it's been a game of detachment, building nearly impenetrable walls, defending herself against a potentially very painful sadness & heartbreak when, inevitably, she uproots and starts again elsewhere. She's simply not strong enough to have deep feelings for more than a few people (namely, romantic partners, but even friends fall into this category) when she knows her time with them is temporary. Maybe that partly explains her strong personality? It helps her quickly weed out those who won't stick around; she can know right off, or nearly, whether or not to invest any surface emotion and energy. S'true, there are certainly flaws in this strategy, but she's gotten on comfortable enough in its employ, until... you.
It seems the time for strategy re-thinking has commenced.
You got under her skin. She let you get into her head. For some reasons, mostly unknown...of all the people whose paths she'd crossed, she knew! Yours in particular would probably be the shortest, most fleeting (simply based on past unlucky okcupid encounters, your traveler status...nothing in her old play-by-plays pointed to "Yes! This one's a keeper! Let your guard down, Honey!" Which is why she was so irrationally saddened that Tuesday night of subway exit miscommunication.). Blame it on the weather, the moon's phase, the tilt of the planet, the atmospheric or barometric pressure, what she ate for breakfast, a particular olfactory stimulation, female hormones... she felt what she felt, for you and you alone. And what she felt, in her own self, regardless of whether you were feeling something of the same, was rare.
Chalk it up to a gross misinterpretationof actions and words, do what you gotta do for your own self.
THIS. This/that/these/those messages & photo, is what she had to do. Making a move, however risky, when she feels something. Telling people how she feels when she's little or nothing to lose and everything to gain. Having a little fun with someone who clearly also likes to have fun, pushing it pushing it pushing it until they tell her (or give her silence) to stop. She likes to test people. See if her energy is worth expending. That is what she does.
Tell yourself "she took it wrong," if that's what you need to do, but don't tell her; she's already surmised as much. She saw You, or the You she wanted to see.