Made mistake while filing gstr 3b

Please help me,

I filled GSTR 3B todat and i entered outward supply tax but forgot to enter input tax credit. Because of this i have to pay 13k extra tax.

There is no option to modify this as i have submitted the returns. Now i want to know if this 13k is a loss for me or will i get it back when i file my next month return.

Thank you