How can you tell the difference between paranoia and worry?

I go through a lot of periods where I think my coworkers hate me and are trying to get me fired. My brain is on the constant lookout for proof. The fears affect everything I do. The thoughts cause a ton of anxiety and ruminating and fear. I want to sleep forever to escape the thoughts.

During the time where I'm not completely consumed with the thoughts, I realize that other people don't think about me that much. They're busy living their own complicated lives. Those rational thoughts don't last for long.

What if things that are happening point to the idea that they're trying to get my fired? Or what if these things are not happening and I'm being paranoid? How do you know if the bad things are actually true? It's not like I can ask one of these people if my thoughts are true.