Right that makes sense, there are a number of apps to manage you mobile phone, including the ability for it to give you a GPS location of it, and emit an audio sound should you lose it around the house. The apps available for this are vast, but Wheres My Droid is probably one of the most known.
If you go to Google Play on the phone,
Click the magnifying glass at the top right, Search for "lost mobile"
You will have many apps you can try, if you want to use the one above search for "wheres my droid"
Click the icon, then click install.
You may be asked to confirm the install as it needs access to your phone GPS and 3G to allow you to access it via your PC.
Once installed go to the app, and register, it will then explain what website you need to login to to control you mobile phone.
I hope this helps, should you have any further questions please get in touch, I would appreciate if you could rate the level of service received today.