Help phone using too much data?

[EricaElite]

Earlier today I got a message from AT&T warning me I've used 90% of my data. I have the 2GB data plan. I checked how many days I had left in my billing cycle and it's only been 4 days since my billing cycle started!
Normally, I don't ever go over half of my plan, and I haven't been using it more than usual. I haven't bought any new apps either.
Here's the apps I've downloaded:
Tumblr, Days Left Widget, Twitter, Foursquare, Alchemy, SwiftKey X, and Pinterest.
I frequently exit all my active applications using the Program Monitor widget.
Is there any way I can see my data usage or somehow figure out whats been using my data?

 

[misterrunon]

get 3g watchdog.. you can also get the at&t app to monitor your usage rate from the phone.

 

[schwenger]

The stock weather widget apparently updates too much and uses a lot of bandwidth, check your widget refresh intervals. Tumblr uses a lot of data if you constantly refreshing the pictures though.

 

[misterrunon]

also, consider getting the "data switch" widget. once you turn it off, android can't run any data in the back ground.. and it's a widget, so very convenient to turn on/off.