How you know you've been playing CS too much?

You tell someone at a bar you were in the CS alpha and made a mod with Gooseman and they say "what, like, way back in the days of 1.6?" quickly followed by "Who's Gooseman?" and you suddenly realize you started playing CS 3 years before they were born. You check steam and realize you are well over 10,000 hours of CS deep. There are only 8760 hours in a year and steam didn't launch until the end of 2003.

We didn't have a LAN hour counting, broadband internet was way too costly for gaming even at the time Steam came out in western Europe.

You can actually check the fact that almost all early Steam accounts were, invariably, accounts from USA-UK-Canada.