Unhappy [Q] strange camera problem

hi guys...i had a slider flex cable problem recently.. so replaced the flex cable with a friend's help and by following youtube vids..now although my slider and screen are back to normal I've a strange and peculiar problem of which i never heard of and still couldnt find any solution to..my camera app is acting totally weird ..it can record a video and play it but it cant take a pic..i mean it appears to click a pic..but i can't review it and it doesn't even appear anywhere in the gallery( unlike the vid )..and whats more strange is the front cam takes pics and saves in the sd only the rear cam is having the problem and also the camera app becomes unresponsive afterwards...

list of stuff i checked

1.checked with different sd cards
2. tried other camera apps..same result
3. changed roms/kernels
4.fully re-flashed stock re locked bootloader
5.took it to the service center ..they couldnt figure out any thing with the camera
6.a local repair guy told there might be a problem with short circuit stuff on the pcb?

i even checkd with the xperia diagnostic tool ..all the sensors..touches..touchpads ..evrythings working..but whenever i click on camera it fcs.

and now even the phone heats up quickly(38 deg Celsius@ battery defender app) with a little browsing,chatting on whatsapp and while charging..and the battery drains out too much even on stock gb ...Please please help me out!!