Samuel Chiltern answered
No, you don't belong in a mental hospital on this basis alone. For one thing, you've correctly identified these thoughts as 'crazy', and you know that they are just thoughts, and have no basis in reality.
The Distinction Between Imagination and Reality
I would be a lot more concerned if you were having these thoughts without realising that they were illogical - and even more worried if you were to act on these thoughts. If you posed a danger to yourself - or other people - then that would form a basis for admission to a psychiatric hospital.
Dreams and the Subconscious Mind
We've all had dreams before, and the content of some of those dreams could only be classified as crazy. Although nobody fully understands how or why we dream, we know that dreams are a product of our sub-conscious mind.
Since the process of sleeping sedates the conscious mind, many of the thoughts and feelings that our consciousness normally suppresses can rise to the surface while we are asleep. This could be why our dreams so often reflect our fears, and other undesirable thoughts.
Crazy Thoughts Don't Need to be Stopped, or Suppressed
I don't think there's any harm in allowing undesirable thoughts to surface while we are awake. The only danger arises when we come to believe in these thoughts, and to act upon them.
Ultimately, we are just talking about thoughts here, and they alone cannot harm you. It's fine to let them pass of their own accord, without attaching an emotional response to them.
You could even allow your creative mind free reign, and draw upon those thoughts as inspiration for creative writing or drawing.
The Distinction Between Imagination and Reality
I would be a lot more concerned if you were having these thoughts without realising that they were illogical - and even more worried if you were to act on these thoughts. If you posed a danger to yourself - or other people - then that would form a basis for admission to a psychiatric hospital.
Dreams and the Subconscious Mind
We've all had dreams before, and the content of some of those dreams could only be classified as crazy. Although nobody fully understands how or why we dream, we know that dreams are a product of our sub-conscious mind.
Since the process of sleeping sedates the conscious mind, many of the thoughts and feelings that our consciousness normally suppresses can rise to the surface while we are asleep. This could be why our dreams so often reflect our fears, and other undesirable thoughts.
Crazy Thoughts Don't Need to be Stopped, or Suppressed
I don't think there's any harm in allowing undesirable thoughts to surface while we are awake. The only danger arises when we come to believe in these thoughts, and to act upon them.
Ultimately, we are just talking about thoughts here, and they alone cannot harm you. It's fine to let them pass of their own accord, without attaching an emotional response to them.
You could even allow your creative mind free reign, and draw upon those thoughts as inspiration for creative writing or drawing.