IPhone 4s using huge amounts of data WHEN NOTHING IS OPEN?

I have had my iPhone 4s since October 2011. (Note, I have NOT downloaded the iOS6 as I like my google maps just fine.)

My data plan is 1G per month. Up until last October 2012 I had never even come close to my monthly allotted usage. However, last month I went Way over. I downloaded 'My Data Manager' at the suggestion of my phone company (Telus Mobility Alberta) and I'm seeing random huge data dumps.

For instance, since 2200 hrs last night I have only received 1 text message on my phone, all the applications were closed out (nothing running off-screen) and the phone was in the charger while I was in bed. I checked my data manager this morning and somehow I used 333 MB of data. WHILE I WAS ASLEEP AND NOT USING THE PHONE.

Does anyone know what might be causing this? Or how to figure out just what this is?

It could be roaming… I think you may have a problem similar to me, as soon as i turn on data, my prepaid credit SAPS LIKE HELL even if i'm not using it… Quite worrying:/

Follow this link.might be you will find the solution: http://forums.att.com/...-p/1963905