Testifying in court for falsely accusing someone?

I will plan to testify in court for false allegations i lied about my brother and said he hit my car with his and chased me with a knife when he didnt instead i chased him with my car to ure he got arrested when tired to leave after we fought. He made me sooo angry and wanted him arrested and now I feel guilty for what i did; the state of California is charging him with attempt murder for the false allegation of hitting me with his car and knife part that i said. I feel so bad for doing this to him now i have to go to the prelim since i was served with a subpoena. IN do plan to testify that i lied does anyone know the California laws for false allegation? Will i get arrested? and when i do go too court does he get dismissed or does the District attorney have the right to continue pressing charges for my false allegations which is quite impossible but please help answer my questions. i have court Wens. next week 3 of Sept.