Your score does not drop when you fully pay off a credit card. If you pay your balance in full before the due date, not only are you not charged interest for that month, but your credit score is likely to go up due to making a payment on time. I used to carry a balance but have been paying it off monthly for many years now and my score is higher.
If you close an account, the total amount of credit you have decreases and your score may drop, however this is often transient. It's not useful to worry about your score week to week unless there's an obvious problem, follow it over the long term instead.