Is my pressure cooker good for the trash bin?
No, you don't need to rash this pressure cooker.  This is only discoloration of the top layer of the stainless steel.  Just polish with a stainless steel cleaner, scouring powder, or barkeeper's friend and it will come right off.

Next time make sure you have enough liquid to bring your cooker to pressure, and when browning meat, if it sticks simply add cold water to the hot pressure cooker.  Attack it with a spatula to lift-up any browned or burned bits - then incorporate them in the sauce. : )