You can (and will) think yourself into any state of consciousness that you want.
The key is thinking about it, you will have to use your intellect to craft whatever it is that you want.
Even if you seek an altered state by using a substance, even that experience will be crafted by the particular state of consciousness that you are in; fear will most likely not resulted in a pleasant trip.
Anxiety is probably worse that fear, since we know are fears and in that they can be tamed.
Anxiety strikes at any moment and without warning, hence the term of it "attacking" sometimes out of the clear blue.
Happiness has gotten way to much good press.
The pursuit of happiness being the capital T "The" goal for humanity is nowhere close to being the reality of the situation.
Happiness is only a temporary state like fear or anxiety,
Choose to go beyond all three if you like; it is very much possible to be above your "feelings" since, first of all, you are already above your feelings by your very existence.
Let me be very clear with my wording. I am using the word feeling as a synonym for emotion as something which is mind-created.
The body of course has the feeling that comes through sensation, which is a different matter; I am not saying that the body can go beyond feeling as if you will not be able to feel a pin prick your skin if you just meditate hard enough.
No need for that, but your "emotions" can be controlled.
How do you do that?
Don't control them.
When you let them "go" you will not get in the way of them and they will have no influence; they will come and go.
Trying to control your emotions puts unnecessary concern on something so trivial. It is like trying to solve complex systematic engineering problems using elementary school arithmetic.
Which is interesting given that our most erudite supercomputers run on a language of "ones" and "zeroes".
Fascinating, ain't it?