Oh my poor kitty....this is not good.?

last night i got to drinkin a little and i got the idea that it would be funny to play a joke on my cat. so i went number 2 in his littler box and watched for him to go in there. he went in the box and came back out with a weird look on his face and his eyes were huge. he has not acted right since. i can only think that maybe he thinks there is a really big cat in the house somewhere and now he is nervous? what do you think? i know i know i am a retard for doing it but like i said i was drinkin a bit and i got bored, im sorry.