3 days into the month usage meter already at 90% of 1.2TB

I received an alert email from Xfinity telling me that my usage meter is already at 90% of the allowed limit, 1.2TB. I checked xfinity.com/usagemeter, and here is the data:

But it has only been 3 days into the month of April, and there is no way I could have consumed 1178GB in 72 hours. It is just ridiculous! Maybe the meter wasn't reset at the beginning of the month???