Writing Pains

I need to write.

Ok, that does not seem like a hard problem to solve, right? Just write you say? Well... I can't seem to find the words.
I have the stories, I am seeing the characters. They are all running like film strips in my head. But when I pick up my pen, or sit down at the computer to type, the words disappear. The characters are jumbling up and nothing seems clear.

I guess this is some kind of writer's block? Ugh.

It is frustrating me to no end. I need to write these stories, I need to get the film strips to stop running, they are starting to drive me nuts because they are on loop and running into each other.

The only way I know how to make it stop is to write it out. Just trying to work through it and writing what I can is not helping. The more I write the wrong words the more insistent my characters are getting. Angry imaginary people are very hard to get rid of.

I just want to get it all out make the imaginary people happy and myself sane(ish) again.