No, insomnia is not a phobia of sleep.
Although unfortunately when sleep starts to become poor it’s quite common for people to fear going to bed because they are worried about what happens to them at night sleep problems like insomnia are usually a habitual problem
So they are effectively a different pattern. Your brain just got used to a very different pattern of sleeping…
Even though you wouldn’t consider it a pattern your brain does. That is why nothing’s changing and in order to treat it we have to retrain your brain to sleep.
Whilst a fear of sleeping can certainly be a trigger of this problem or it could be a side effect of it. It is not usually the act of not sleeping that comes from a lack of a sleep drive over time.