When I feel like that the only two things that ever help are talking to people and grounding exercises. Talking to people.. if there isn't anyone then 7cups is a website where you can usually have a live chat. Grounding exercises are focusing on your senses. Like trying to notice and list out loud all the different colours you see, the smells you can smell, touching things to notice how they feel, warm or cold, soft or hard... etc. It puts you back in the reality of the moment as it is, instead of the emotional torment inside you are in the world.