There are going to be some issues forcing him out since there was no formal written agreement. The email doesn't count as a written agreement since both parties didn't have an opportunity to read it, make any changes, and then sign it. What this means is that you will be bound by the terms of it but the other side will not necessarily be bound.
There are two problems that I see immediately.
1) You stated an amount of rent but didn't give a due date and therefore they can never be overdue.
2) You told them they can stay until November so if you try to evict them before November the court may, and likely will, dismiss the eviction.
I'd suggest you take the email to a local attorney, have them review it and tell you what they think the local judge will do. If you file for an eviction and the other side hires an attorney and the eviction is denied they can make a counterclaim for their attorney's fees.
If you hadn't done the email you would be in better shape since at that point it was a month-to-month tenancy and you would had just had to give them the one month notice that you were not going to continue the lease next month.
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