I got mild serotonin syndrome because of a small amount of paracetamol and tramadol.

Basically i have acute pancreatitis and the doctor prescribed me tramadol, i got the med for a brand called ultram, each pill contains 37.5 mg tramadol and 300 mg paracetamol.

Had a flare up in pain yesterday and took a pill and half a pill half an hour after the first pill. Moments later i started feeling extreme anxiety and started having most of the symptoms of mild serotonin syndrome like feeling hot, confusion, muscle twitching etc. Is it because of a weird reaction b/w Paracetamol and Tramadol?