You try to build your own TARDIS. [My brother's friend did this, it was really awesome but you couldn't fit more than one person inside it.
Whenever you get stomach cramps, you clutch your abdomen and yell "I'm regenerating!"
When someone tells you the date, you reply "Again?"
You're terrified of people with Bluetooth earpieces.
You spend hours trying to work out "reverse the polarity of the neutron flow."
You are convinced that you are a Time Lord/companion who has lost their memory/the only surviving Human-Time Lord Biological Metacrisis.
When it snows, you build a Snow Dalek instead of Snowman.
You watched Nan's Christmas Carol just because it had three whole Doctor Who actors in it [Catherine Tate, David Tennant and Roger Lloyd Pack]. (Though this might just be for people who live in the UK, as I don't know if you can watch The Catherine Tate Show in the US.)
Out of my three pairs of shoes that I wear constantly (all converse), two of them are the pairs worn by Ten.
I even spent extra effort to hunt down the beige ones, which are actually limited edition converse from 1990, the last run that were made in the US from all natural materials. They came with puff paint, unopened since before I was born. It was so cool.
-You have the sound of the TARDIS coming and going as your text alert sound, and it makes you so much more excited to get texts although every single time you instinctively look around you in case there is a blue police box appearing.
-You now freak out about having been on Mount Vesuvius more for the fact that the Doctor stood where you had rather than the actual historical event.
Several things have been 'ruined' for you, including, but not limited to:
-Shadows/the dark (I watched that one in the dark at night, alone... oh, that was fun. Plus my friend on AIM kept texting me going "Hey, who turned out the lights?")
-Under your bed
-Christmas (although that one is also a good thing, especially in London)
-Pepper shakers (come on, the Daleks totally look like 'em)