Dont want to hold back

There is so many things stressing me out and i just want to let go and feel that blade against my skin. I want peace of mind for just a couple minutes. The other thing is that my nightmare was that I lost control in front of my dad who knows nothing about me being a cutter and I just grabbed a knife and started cutting myself up. I kept saying this is what you do to me; over and over again. My cousin had to grab me and force my hands to stop. With that nightmare going through my head I’m feeling really frazzled and jittery. The worst part right now is that I’m at work and have to work with knives. What do I do?