You should definitely check the Landlord/Tenant Laws for your area because if you don't have a signed lease, your landlord may not be required to do a formal eviction. While you may feel not being required to sign a lease is a good thing because you aren't bound to anything, leases are used to protect the rights of both the landlord and the tenant.
The Landlord's asking the same question... Contact Frederick Co / City Housing Authority... I'm not an attorney, but it appears you've made a verbal contract which should be enforceable, though messy, time consuming, & expensive.. Ask your Attorney
Without a formal written lease, your arrangement is likely considered month-to-month. If this is the case, all the landlord has to do is provide you with adequate notice. I would consider identifying another rental.....sooner than later!