Sick and tired of my dishonest landlord.

I am sick and tired of dealing with my dishonest landlord. Today she put a notice on my door dated 12/1/16 saying that my lease expires 12/31/16 and that if I want to stay the rent for 1/1/17 (which I have already paid.) is going to go up $50 if I sign a new lease and $125 if I go month to month. Since she lied about the date of the notice it looks like I didn't sign a new lease and shorted them on the rent $125. I am not even sure if the lease actually expired because the last lease I signed was in March or April but since I was month to month for a couple of months she might have made the date to end 12/31/16 - unfortunately I can't find the lease and am having to go through all my paperwork and nooks and crannies in the house to find it since II can't be sure she didn't change the end date on her copy.

Any suggestions on what I should do?