I'm not sure if it's 'normal', but I wouldn't worry about it unless it goes on for two or more days. (Wouldn't you be hurting too? He's probably trying to punish you for taking him to the vet's! Haha )
My cat has been having (by has been, I mean for appx. 8 months) a very green, mucus-like substance in his eyes. Sometimes clear, watery stuff drips almost like he's crying, but they're very big drops. Underneath Tommy's eyes, he also has crust and every day I have to clean out his eyes for him...