Hey Dawn22,
The discounted promotional offering on the website is applied to new accounts upon sign-up, for those who opt for this over the 30 day free trial.
As you have subscribed via the iTunes store, your billing will be via Apple who are a third-party re-seller of QuickBooks, and so prices may vary to our own. It is likely you are unable to use the account on the PC as the trial is expired - to reactivate, you would need to subscribe via the iTunes store :)