Don’t worry too much.
Unless your dog has a clotting disorder (and you would probably already know about this), the nail will stop bleeding on its own.
Firm pressure slows the blood flow through the injury and allows the platelets (components of the blood responsible for clotting) to stick to the wound edges and do their job. Hold a clean cloth on the bleeding nail, if your dog will tolerate it. Press firmly on the bleeding nail tip for as long your dog will let you.
Why Does My Dog’s Nail Bleed When I Cut It?
Inside each nail on a dog, there is a vein called “the quick.” If you cut this vein, the nail will bleed. This is why its important to learn how to safely cut your dogs nails. Using the correct technique will make the experience easier for both you and your dog. Lets start out with the basics.
On white nails: It is quite easy to spot the quick on white nails because it shows up as a red dot against a cross-section of the nail and as a skinny, pink line through the core of the nail. As you cut a white nail, bit by bit, the quick will begin to appear as a tiny red dot. That is the beginning of the vein, and the cutting should stop before you cut too deeply.
On black nails: Seeing the quick on black nails can be hard. When cutting them, the interior cross-section of the nail will be whitish or grey and oval-shaped. It is here that the beginning of the quick will look like a tiny black dot. Cut small layers off to get an idea of how far back the quick is. If you cannot see the quick, sometimes it is better to do five small cuts for each nail instead of taking the chance and cutting off one large chunk.
How bad does cutting the quick hurt?
To cut into the quick is very painful and it will be a shock to your dog and therefore instinct will have the dog react not only by pulling immediately away but biting to get its paw free.