that great. a sigh of relief for you. trust me the call center or the staff wont even know brief details about it. no need to wait for it you can pay the amount right away. better for you to wait and go as per their rules. Regarding cancellation of card i prefer not to cancel it just clear the dues. and keep it aside. you might needs it anytime in future. For overspending stress and tension you can contact the same number i gave you and tell them to reduce you credit limit. that would be great. Right now dont discuss anything regarding cancellation with them. Just clear your dues. Thats all.
Remember If you pay your dues on or before time you are a Bad customer to a bank.