My son is having trouble focusing. He said it feels like he goes into a daze like stare and has to blink to get his focus back. Also has discomfort behind his eyes. He went to an urgent care last night and was given a zpak which he started at 8 pm. He has had a cold for about 1 week and started getting really congested a few days ago. He was self treating with Mucinex prior to the zpak.