My question involves an eviction in the state of: California

First and foremost thanks for reading my thread greatly appreciate any feedback!!

I currently rent (month-2-month, no lease?) a room in a private residence with 3 others tenets (none of which are the landlord) for the past year and a half. Prior to one of the tenets moving out I paid utilities to him and rent to the LL, with that tenet moving out (1 week notice) the utilities were shutoff without prior written agreement with other tenets or LL on how to keep utilities on. I do not wish to have utilities in my name with others also occupying the same house. The LL put the electric in her name but wont budge on anything else and since the water and gas has been shutoff as of 2-4-2014.
As a result i have held rent until said utilities are restored. The LL notified me via a text message on (2-5-2014) saying I have to leave for non-payment of rent. The LL has since repeatedly sent text messages saying the locks will be changed on 2-9-2014 and I have no rights because i am renting a room. So my questions are.

1. Is a text message good enough to qualify as a written notice?
2. Am i considered a lodger as opposed to a tenet due to renting a room and not the whole house and what rights do i have if i am a lodger?
3.Do i have a right to withhold rent due to utility shutoff?
4. Can the LL legally change my locks and keep me out of the residents?
5. The LL said i signed a lease which i have no recollection and know i didn't. but wont bring a copy of and refuses to provide proof after multiple attempts. Is this all legal?


Again greatly appreciate any feedback. I don't wish to break any laws and will pay whatever i have too no problem but i will not put utilities in my name.