I Just Signed A New Contract With Bell Mobility And Am Getting Charged?

Yesterday I bought an iphone 5s with a plan with Bell.
I realized yesterday that the contract said that I'm gonna get my bill on Oct 19th. I also noticed that it said that I started my contract on September 19th, but I only got the phone yesterday with the contract.

Should I call and tell Bell about this? I don't want to pay for a month I never used.

Well, durr.
Why are you going to pay for a month that never happened?

Go see if you can dispute the matter.