Brace soreness. The first time you get braces you will start to get sore about 5 hours later. That soreness will increase a little more each day for the first 3 days and will last for 1-2 weeks but it's not a bad pain just sore and achey.
Should be minimal. There can be some discomfort with braces because it is putting force on the teeth that are being moved. There can be some irritation to the cheecks and gums a little at first as they are getting used to them as well. It will be different and unusual but you will be fine.
Mild. Pain is normally pretty mild with the great light wires that are used today. In the past there was a lot more discomfort because the wires were very stiff in comparison. Many do not require any pain medication.
Manageable. My adult patients tell me that it's more ache than pain, like having a headache in your mouth. Keep your gums healthy, don't damage your braces, take an analgesic, rinse with salt water, and the soreness will soon go away. Ask your orthodontic specialist for pain-management instructions that are tailored to your individual situation.