Feelings of pressure over forehead or tightness around the forehead, headache is common in stress.  Since it is happening for the last 4 years & is troublesome to you, you can take help of a psychologist or psychiatrist who will evaluate you in detail & help suggest ways to tackle stress if that is evaluated to be the cause.

What you might be experiencing is a sign of Depression or Anxiety. You should consult a Clinical Psychologist in order to get a psychological evaluation done. Post evaluation therapy sessions will begin.

There could have been a triggering event that is leading to pressure. It is essental that you understand and pin point about the root cause of the pressure ans stress in your mind. N like you said. It so happens that when our mind is overcrowded with negative thoughts, it feels as if it hs freezed and cant think through. Let us first figure out what is causing the pressure. If you can give a detailed history of the events, itciuld be more beneficial.

  First assess urself for atypical depression After that will plan for treatment I Can help u if u agree