Try soaking it in warm Epsom salts, do not puncture it, you might get an infection. If it does not go away on its own and continues to hurt, have the doctor take care of it.
Heat up a safety pin, and try to poke a small hole in your nail. My dad did that when I had a blood blister under my fingernail and it helped immediatley.
i had the same thing about two years ago and boy it was so painful... for pain the i tried to not walk on it as much i used a bandage to keep the blood from comeing out. in a cupole of weeks it stoped bleeding and my toenail fell off and it really sucked but the pain was gone and i could walk around and not feel uncomfortable. Are sure that it's a blister beacsue it might be that your toenail was hit on something and in that case your toenail will start to bleed and the blood would stay underneath for some time and once the toenail falls off it will start growning back in no time.