Well to the first question I guess you used that much data already. Did Koodo send you this warning or was it your phone? It's possible that self-serve hasn't updated yet to reflect your latest usage. You might h wi-fi assist turned on which might account for your high usage. You can use the phone's data counter or a third party app to measure and track data usage
Kathy - when you say "my account says I've used just under 200mb", where do you see this information? Looking at your account I can see that you've used 460mb of your allotted 500mb for the month. The large majority of this was consumed this weekend (both yesterday and today).