Why isn't my rear camera or led light/flashlight working?

I dropped my 4s just over a month ago and the front screen cracked ( i have not got this repaired...YET) i tried accessing my back camera and i saw that it no longer worked ( the first few days after the incident it worked but had lines/smears/smudges) After that it just began freezing and i have had no access to it whatsoever since.. I also discovered just last yesterday that my flash-light tool (torch in the swipe up menu) decided to stop working. I want to know if i do get my screen replaced normally(digitalizer&LCD etc.) that these problems would be fixed?

I have been told by tech people a range of different answers and some places want to charge me alot of extra money for this problem ( like double the usual amount of replacing my screen) The touch on the phone and my front camera are still immaculate ( the camera takes a little while to work, but it does)as along with everything else..

I am really really wanting to know if its worth the extra money or if i should just upgrade. PLEASE HELP ME!!!