Anxiety attacks

Do you ever just have an over whelming feeling of sadness? Like a blanket that just covers you. The anxiety takes over. And your just sitting there trying to pull yourself out. But you have a Tight chest, heavy breathing, overwhelming feeling of grief.  And ten mins ago you were completely fine? Happy even? It's almost like an outer body experience. It's the only way I can explain it. And I feel this way about 4x at least a week. I have nothing to be sad about but I'm still am. I'm seriously so over feeling this way. And I don't know what anyone can do to make me feel better like I said I have the best life ever. And i just feel so ungrateful . I feel like POS.