i want to sue my administrator but not sure where to start i need help

i work for an assisted living home in carmichael, ca i was put on call back in april but not for a good reason i was called into work maybe 2times to work. Havent been called in since but she has hired other workers. I'm still on her payroll and havent been fired but she has notified other workers that i am not to be in the building at all. the administrator has never talk to me about this or showed that she has a problem with me but i feel like im being bullied, harrassed, descriminated and she is defaming my name. By telling residents and workers that i got let go for stealing i was never fired im still on their payroll. I seem to be the only one she treats like this others have quit and had confrontations with her and can still enter the facility but im not allowed in, dont know why and she has never talk to me about this situationl