Is my iPhone 7 supposed to wobble when sitting on the back of the phone on the table? Is that just the camera bump?

If you don't have a case on the phone, yes, it will wobble a bit as the camera sticks out.

iphone 7 is aluminium so you could have bent it in your pocket.

Try it on a table top with the camera hanging over the edge of the table. It should be flat.

If it is bent there is no remedy.

PS always fit a screen protector and always place a phone face down. You can replace the screen protector but not the camera sapphire glass.