Ask a landlord-tenant lawyer and get answers ASAP
I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
What state are you in?
Thank you. It'll just take me a couple of minutes to find the statutes.
The default position in the law is that, when a person moves into your home with your consent, whether you're still living there or not, they're a tenant and have tenant's rights. Ohio Rev. Code, Section 5321.01. When you're renting from someone else, that makes you a sub-landlord and him your subtenant. And that also means he's generally entitled to 30 days notice before being asked to leave. Section 5321.17.
There are some states that have laws to protect victims of domestic violence in rental situations, but Ohio is unfortunately not one of them. You can absolutely call the police to report what happened and you can seek a restraining order against your boyfriend for your own protection. But you're not allowed to simply change the locks, because that's an illegal eviction. He could sue you for damages, plus a court order to get back in, and that puts you in a worse position than you're in now. You may also want to contact the Ohio Domestic Violence Network to see if they can help you.