Many times it happens to me that I do not know what I am feeling (if it is negative or positive) I only feel an immense desire to expel what I have inside and I cannot.  A cry without tears, I suppose.  I despair because I feel like I can't vent.  Worst of all, no one believes that I just can't.  I've been like this for months.  The last time I cried it was very sudden and it only took me a couple of minutes.  I hope if someone else is experiencing this that they can overcome it, because it is frustrating af.