Do you remember that you asked me " second day you will sleep with me?" It's not good question for Thai people, especially Thai lady. It means that person not to honor and very insult to Thai lady.
Normally, if anyone asking questions about this with me, I will not answer and never talk to that person. But for you, I think you different from other people, you don't know and also didn't understand the tradition and culture of Thai.
It's normal for you but for me, it's harder than a kiss. Actually, it's not wrong, just like you said it's not the end of the world. But for Thai people were against a tradition so was spoil one's reputation and insult dignity of that woman