What do I do when I think I've cut too deep?

You don't cut in the first place. You just don'y do it. Or you die. Either one. Which ever works for you

If blood is pumping out your wound in time to your heart beat it's likely you've hit an artery and you should call an ambulance to get yourself to hospital as quickly as you can. If the wound has got something embedded in it or will not stop bleeding after 10 minutes it's also important that you get yourself to hospital.

First things first, you need to put your blade down. That's the most important thing, I cannot stress it enough. Step two, call 9-1-1. If you even suspect for a second that you've cut too deep, you need to get medical attention.

If you're in doubt you should always seek medical attention. Cutting as a coping mechanism should always be the very last resort in the first place but if you've already done it then make sure to clean it thoroughly with clean, warm water and salt. Make sure the blood is clotting and if it isn't then talk to a trusted adult. If the wound keeps bleeding put pressure on it, either with just your hand or if you have access to one a clean bandage. The section 'When to seek medical advice' on this page is very useful: http://www.nhs.uk/chq/Pages/1054.aspx?CategoryID=72&

Immediately wash the cut and bandage it. Apply pressure to the cut and i'd say if it still bleeding, not necessarily heavily, after about 30 minutes OR if you feel lightheaded before that immediately call 911 or someone to take you to the hospital.

Immediately contact a trusted adult and/or call 911 and receive first aid. Urgency is crucial. It can be scary but you even if you're on the fence, you should seek help.

First call 911 or an emergency contact, you need someone who can get there as fast as possible. Secondly you should stop the bleeding; put pressure on the wound and get it above your heart. But remember to breath, don't panic yourself further that will only cause more problems in the end.

If you think you've cut do deep, call 911 as soon as possible. It is best to clean up the wound as best as possible, wrap something to contain the blood. Keep your cut upward and raise it up to keep the bloodflow from getting too worse. Try and calm yourself down by breathing

Go to the emergency department and let them take a look at it, you might need stitches. Deep cuts can lead to death.

Get to a hospital asap! Your health is at stake regardless of cutting too deep or not. You need to get help for your wound if you've cut too deep!