Ok so I am a teenage girl. The other day, I met a guy in his early 20s. He is friends with someone in family, and we were just causally talking. When I was leaving, I said to him, "I like you, your really nice!" I meant that like I like his personality, not that I had a crush on him. After I said that to him, he started thinking I was weird. Is that a weird thing to say to someone? I was just complementing him!
No, what you said was a very polite and nice thing to say. You do not know what he was thinking for sure, so don't go reading things into him that are not there. What you said to him was fine and if he is also a nice person, he would appreciate that. If he thinks a compliment like that is weird, then the crowd he is used to is not a crowd you would fit into.
You did nothing wrong. You said what you felt and it is sure not weird or strange. On the contrary: It is: nice sensitive polite true words. Ignore what he said. He has some problem (or never met nice / honest / open / true people like you).
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