poisoned?

My baby was missing for 2 days, tonight he appeared meowing non-stop asking to leave again, despite the fact there is a down-pour outside!

I gave him some food he grabbed a few bytes to eat ( Kitekat ), then continued to run around, meow and marking his territory in the HOUSE! I gave him some ham he ate a tiny bit and then asked to go away again.

His pupils were so dilated that i could not even see any other part of his eyes.

I have to admit he was always a fudged-up little boy, but this was off the map.

So i was thinking is it possible that someone might have poisoned him and he is in pain or is he upset that rain is washing away his markings or what could it be?