I think we all go through that at some point to a greater or lesser extent, and in these cases I think it is important to find the reasons: is it the place where I am, the job, the people, etc... Identify what makes you feel that way in order to avoid that abyss pulling you down.
As you say, time flies, and if things are not working it is better to take action now and change what needs to be changed in your life.
Go on a trip, if it is to a natural place much better, that always helps hehehe, a hug!