This is a powerful powerful thought that is hard to over come. Do like the others have said. Push the thoughts out of your mind as best that you can. If you do not gain control head for the hospital. Call a hotline or family member. Try to keep yourself safe. I have been in your shoes more than once. You are not fighting suicide you are fight the depression that is taking over your thoughts. I know that you can do this.... Fighting back might just give you the edge you are looking for.

First thing to do: if you know your plan, get rid of it. Take it out of the house. And please go see a doctor. Very sorry you have to go though this, I know how painful it can be, wish I was there to help you. I hope that you have a better tomorrow.