Occasional asymmetrical blinking in baby

Please help! My baby is 3 month old. I noticed that sometimes ( I saw it 2 or 3 times), he closes his left eye more than the right one. It is like he is blinking, but the left eye closes completely, and the right one stays slightly open. And he doesn't open his eyes right away. The eye stays closed for like 1 or 2 seconds. First time I saw this happening he was around 2 month. And now. It is scaring me. What could it be? Happened to anyone? Will he outgrow it?

Please note that he has a clogged tear duct in the right eye, not sure if this could be related..