Dreaming of dead fish on bed:
One dream interpretation is about bad news
The dream interpretation depends on your circumstances. This dream is a warning of bad news, if you’re in a situation of being sick, or if you’re out at sea. When you’re out in the ocean, a dead fish on your bed means something happened in the sea which killed the fish. Natural calamities at sea can be earthquake, poisoning from algae or etc.
A different dream interpretation of a dead fish on a bed
The fish is a symbol of spiritual power. Seeing a dead fish can mean the former spiritual power is dead or not working. When the spiritual power comes in the form of a fish, it means that it still requires the basic conditions that the physical form depends on. That is, the fish needs to be in a body of water, to stay alive. It needs the basic conditions to maintain life, before it can even act with its super power.
A fish out of water dies quickly.
When we combine all the meanings of the individual components of the imagery together, the composite message is complex. The dead fish on the bed can mean the fish died on the bed. Somebody took the fish out of water, to place on the bed. Consequently, it died.
Why would anyone put a fish on a bed? This scene hints of shapeshifting. The fish could have initially appeared in another physical form and shape shifted back into its original form after its death.