Does not matter what you "own" but rather what you have installed. If you have 32 bit, you will get 32bit, 64 to 64 as well. The ONLY way to switch is to perform a Clean Install (wipe all and start over).
Hope that clears it up a bit.
If you want a sure-fire way to find out what architecture you are on, do the following:
Open PowerShell
Type the following command: (Get-WmiObject Win32_OperatingSystem).OSArchitecture
You should see either of the following:
64-bit
32-bit
This will tell you once and for all what you have and will get.