Reset you phone may remove this problem.

My 900 used to take good pictures. Now with all the camera settings at default, the indoor frame scene to take the picture of is very dark. On indoor items the pictures turn out brighter in the center of the object and darker around it . I have adjusted all the various setting - out of default- with fair to poor results. It almost looks like the flash is going off before the picture is taken ?. I hope this makes sense.. Thank you for any help or tips.