Usually there is a pretty wide grace period on those mortgage payments, so if it went to the credit reporting agency you might have been paying at the end of the grace period instead of on the due date. For things like mortgages, financials are very careful in putting a hit on a credit score, and only do when there is a good reason such as a payment made after the grace period.
I'm a bit confused when you say your credit card was taken off you. Universal defaults may cause your rate to increase, but other than that I don't understand why you would have a card taken away.
As a business owner, it is your responsibility to have a handle on your finances, but because you've only recently sorted things out, it would seem like it wasn't just the banks fault.
You are moving in the right direction though, you have your finances in order now, the next step is to look at how you can save more money to make up for that late payment. My blog has some tips on creating a cheap and easy budget here:
* Easy, Cheap, and Quick Basic Budget*by*Financing Your Family
You can also ask questions, we can help you on these forums as well.