Pablo
Reading your opening post there was certainly a major flag or three. Reading the subsequent ones , I would be less alarmed of a scam being perpetuated on you. It really doesn't pass the litmus test of a scam.
However, her not inviting you to her place or to meet some measure of family or friends while you are in her city is a bit telling. It says she doesn't trust you. She may have good reason because you are here posting concerns of your lack of trust of her. This isn't a bad thing but it reeks very little communication between the two of you obviously, because you two don't speak the same language.
On the other hand, you have met her. You should probably decide if you can see yourself moving forward with this woman or do you punt and wait on the next set of downs? A bit of advice, it is considerably more difficult to get to know and learn a woman where neither of you share a common language. It can be done and has been hundreds maybe 10's of millions of times. There are a number of examples on the forums but, one common ingredient is the man has a bigger commitment in time, patience and expense.
If you wish to move forward with this lady you have to break that communication gap and get to know her and she you. Find yourself an interpreter for phone conversation, skype sessions and communicate with her regularly while you get comfortable with each other. Try to learn some of her language and yes, perhaps assisted her financially in learning some english.
This is just another of the pitfalls of dating internationally. It can and will test your metal as a sincere man. Even if you start over and find a woman with english speaking skills, you'll still have another subset of communication barriers and misunderstandings. There are 100's of ways of doing it right and 100's of ways of doing it wrong. For those intent on doing it right one common denominator is never forget, it is still "boy meets girl" trust and relationship are priority.