My gum is covering over my tooth, there is no pain and it wont move. i have braces on(from 2years). should i be concerned? is it infected?

There is no: There is no substitute for a personal clinical evaluation with an x-ray. These types of questions cannot be properly answered with such little information & the inability to personally examine you. If the area in question is all the way back in your mouth, perhaps it's your erupting wisdom tooth. You are under the care of an Orthodontist & hopefully seeing a General Dentist on a regular basis. Ask

Local gingivitis: due to bracket irritation. What you need to realize is that gingivitis is reversible condition. If you don't take care of it now, it will progress into periodontist, bone loss and that is irreversible. Get a professional cleaning by your dentist, brush and floss the area twice per day. Good luck.