Losing performance on change of scene.

Hello
im having a problem. When i start the game in the combat scene (its a fighting style), im having a stable 57-60 fps. but when i start the game from the main menu, im having 45 fps.

now, i tried to trace it back to why it is, and im almost sure that it is because of the camera and rawimage that i use to showcase the characters when selected. however, those thing shouldnt persist when i change scenes i think. im using Scenemanager.loadscene(1) , to change to scene 1, and i think that destroys everything from scene 0?
Even in the main menu im a 25 fps when the rawimage and camera are active, which i think is really for only one active object in camera and only one light source. But when i disable the camera i get back to 60 fps.
Now the thing is, if i start the Mainmenu with the camera disabled, i can run the game at 60fps (in combat mode), but if i start it with the camera enabled, even if i disable the camera, the gameobject where the camera is, the rawimage, or destroy any of those, i still get 45 fps in combat mode.

at this point i have not idea what to do, or how to fix this. im new at unity, so this may be a commom mistake, but i have spent the last 4 hours trying to find what was lagging the poor game.

Can someone help me here?

 

Have you checked the profiler in both cases to see if you can identify the performance drain?

 

This is what came up, it is definetly the camera rendering. but i dont understand why it is rendedring in scene 1, when it should be inactive because the camera is from scene 0