How do I edit info in DS 160 after having booked the appointment and paid the visa fee?

I filled in the DS 160 form about a week ago and booked an appointment (not yet appeared) by paying the visa fee. However, today I realized that I have filled in ‘NO’ when asked about ‘Have you traveled to any country within the last five years?’ in the form. I did an internship abroad and did mention it in the past work experience but mistakenly filled in ‘NO’ when asked the question. Do I need to fill out a new DS 160, repay the visa fee and book a new appointment? Or do I simply fill out a new DS 160 and carry the confirmation page of both the original and the new DS 160 without scheduling the appointment again and repaying the visa fee (as many sites seem to suggest)? Or is there any other way?

It is your choice - the question relates to travel to countries with whom US does not have diplomatic ties such as N Korea or Cuba. I would not worry about it. Best wishes