I don’t wear hijab but a similar thing happened with me also when I was new in this country. I was hanging out with my brother, his french friend and her brother. When it was time to leave and I was saying good bye to every one the french guy just leaned over and kissed my cheek and I instantly slapped him. OMG he was so embarrassed, he didn’t knew what happened and my brother was like 
yeh ki kita kuriye.
Khair when they were gone I was damn angry with my brother that what kind of friends he have, he said that it’s normal for them, it’s just a cultural thing. And I was like why are we so suppose to worry about their cultural values and why aren’t they suppose to respect ours.