Excessive eye blinking. His exam also.

My 3 year old son recently developed the behavior of blinking his eyes frequently and he completely closes his eye lid on both the eyes, shrink it and open it. Recent change at home: I reduced the TV table height to 1 foot as I thought my son would feel neck pain. I observed the excessive eye blinking behavior after that. I am sharing this for your information. I am not sure this is a cause. He took anti-biotic for his cold and fever. During that time, the excessive blinking reduced so much and he did it one or two times. that too once in longer period. I meant the frequency and the no. of time blinking, both reduced that time. We do not see any vision issue. He reads books and writes. He attended his exam also.