Nervous

I start a 40mg dose today and will be starting a 50mg dose of Trazodone for sleep when I go back to work on Thursday since I work overnights most of the week. I’m just a little worried about the risks of serotonin syndrome. How likely is it and what do I look out for? I’ve been on sertraline for years before today. I apologize if I’m not making much sense my mother got me a little nervous and I am just a worrier.