Well I did the same thing couple of mth before. But in my case I had to use 5k.
first month I paid 2.5k
the the following month was 2.5k + (Interest of 3%=75)+ My current Expenses.They only charged interest for the outstanding by the way.

P/s: Banks Make Money when you pay late, because then only they can charge you interest.

Check with you bank for the interest rate and charges.

Hope this helps. Have a nice day.