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