When to "smack" the smack pack?

The question is sort of a "when should I brew after smacking the smack pack". I bought Wyeast liquid yeast today around 4:30. I am planning on brewing tomorrow, so I smacked it thinking it wouldn't incubate for awhile since my house is at about 64 degrees. Low and behold, that thing is blown up like a BALLOON. Do I need to brew tonight, or can I wait until tomorrow? Do I need to brew in the morning (I was planning on waiting until the evening)? This is the first time I've used liquid yeast. I'm brewing a Kolsch with a OG of 1.045 or so...thus I wasn't planning on making a yeast starter.

Thanks!

It'll be fine... But if you change your mind and won't brew for another day or two, just put it in the fridge.

You'll be fine, but better if you make a starter.

"You'll be fine, but better if you make a starter."

Agree completely. Also invest in a stir plate. Montanaandy