Does anyone else??

Does anyone else make up scenarios in their head and actually get paranoid and upset about it? BUT ITS ALL IN YOUR HEAD. I swear I'm not crazy. 
Basically, I had a really tough day at work. I felt like everyone was pissed at me and/or talking bad about me when I left the room. This always happens and I have really bad anxiety and I have no idea how to stop it. I don't know if it's just because I'm on my period or if it's just a feeling or what. 
HELLLP.