What dose it mean when you catch a guy staring at you multiple times?

I had this very short encounter with a guy ( I went up to him and congratulated him on something, and that was it ), and ever since then, I keep catching him looking at me. Mind yoy, I have never seen/ spoken to this guy before. So what dose it mean?
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+1 y
P. s we are both religious ( Christian ) so
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+1 y
The thing is I dont know if he is just staring at me because he thinks I like him ( since I went up to Him and congratulated him ) and he thinks Im ugly and thats why he keeps looking. But then he could also find me familiar and he is just trying to figure out who I am. WHAT SHOULD I THINKK?
What dose it mean when you catch a guy staring at you multiple times?
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