The "Sons of Anarchy" star says he "couldn't transition from Jax Teller to Christian Grey in 48 hours"
Jamie Dornan and Dakota Johnson star in the hotly anticipated erotic film, based the best-selling novel by E.L. James
The adaptation of the hit erotic novel arrives on Valentine's Day
Says leaving film was "pretty heartbreaking"
Former fan fiction author is estimated to have made $95 million last year
Adaptation of hit novel will face off against "Guardians of the Galaxy"