On day 5 of my period and the blood is just like staying inside me and won't drip out???

I'm on day five of my period and I really haven't even had to wear a pad at all because the blood won't even drip out. It's like it's just staying stored in my vagina. If I stick my finger in me and take it out my finger is covered in a lot of blood. I don't understand why the hell it won't drip out????