I took about 250 mg of dextromethorpan and Zoloft (sertraline) 125 mg and 100 mg of trazadone, will this cause serotonin syndrome? I'm worried help?

Dextro OD. Call poison control now at 1-800-222-1222 and ask for their advice asap. Overdose is the concern, not serotonin syndrome. Consider calling 911 and going to the nearest emergency room to play it safe.