tax mess up

I completed the portion of filing the taxes and since i was using the free version i submitted it but, i didnt pay the amount i needed to yet . although i did receive an email saying my order was received an i got an order # but i wanted to change my taxes to married filing separately but im not sure if im gonna mess something up because i am able to change it. but since my first one was sent idk if it’ll mess me up. any input?