Why does this guy keep looking at me?

So I get to my clroom about 15 minutes early every monday and sit outside the room waiting on my own. Well there is is this guy who gets there early as well and he sits further along the corridor waiting outside his clroom. So I always sit waiting and out of the corner of my eye I can always see him looking at me! It is so awkward and if I turn to look at him he quickly turns his head around to look the other way! I always meet up with my friends after the lesson in the reception of my college because I have a half an hour break and he is always hanging out with his friends in the same place and he's always looking at me then too! It makes me so embarred and self conscious! He has never spoken to me, so I don't know why he keeps looking at me?