Fixed the shop. For some reason, the variable shop opened wasn't working (I found that out after several hours of testing), so I deleted it and made a new variable also called shop opened and it worked. Removed the number of gems when shop is opened because it is already next to the pause button MORE BELOW
Also separated the back button and the shop background because when the mouse is hovering over the back button or the shop background, the shop background's brightness is being affected too. BTW, the money set to 999 is in the shop button sprite