Power Button On/Off issue - Button is being pressed alone

Hi,

my power button was stuck so I decided to replace the flex cable.

I did the replacement following the IFixit guide and it was almost a sucess. The button is now working, but sometimes my screen keeps popping like the On/Off button is being pressed, although I'm not pressing it.

What should I do to fix that issue ?

Also, after the replacement, a bug happened with my photos stored. The iphone recognizes that there's data being used by the phone, but the camera roll photos section is empty.

Are those problems related ? How Can I fix that bug ?

Thanks in advance,

Bruno.