Include a clause that states that your manager needs to check your availability before booking modeling jobs. Add a clause that states you are not an employee of the manager but a client paying the manager to do a service for you. State the percentage you will pay from each of your bookings to your manager.
A jammed finger can lead to some complications, including: long-term pain and swelling in the joint, known as traumatic arthritis; stiffness in the finger; weakness in the finger; permanent inability to straighten the finger; deformity of the joint
Listen to @MEade, don't pull it. I had someone pull on my jammed finger because it was crooked. It turned out to be a bad fracture. Hope that isn't your case. I don't know if the pulling on it caused it to heal with a rotational deformity or if it was from the initial jam.