it could be but I doubt it. Usually for seretonin syndrome to happen you would have to be taking a pretty large dose of something. I had seretonin syndrome when I got a bad hit of ecstacy back in my party days, and heres what I experienced, from what I remember (take this with a grain of salt as I WAS under the influence)

I remember my temperature being slightly elevated, I was sweating. IT started off when I was sitting on a couch and suddenly got nauseaus and dizzy, and then I got this weird sensation where my heart is(I now know it was palpitations) and I started getting severe palpitations(enough to almost knock me back off my feet and enough to make me feel a pinch right out to the ends of my fingers and toes with the beat). I remember getting to the ambulance and my pulse was around 140 - 150 or so and skipping. I dunno if I was flushed or not as I was scared half to death. Later at the hospital I started feeling electric like zaps in my joints, I dont really know how to explain it - sort of like a small electrical current was running deep inside a small patch of my joints. This began causing small seizures, almost more like spasms. IT would domino effect, when it started one area it would cause other joints to fire. Yes- thats almost what it was like - it was like my reflexes were being zapped and firing off. I experienced some bleeding in the joints under the skin but minimal. apparently from what I researched the bleeding under the skin has something to do with the fact that seretonin has an effect on red blood cells binding( I cant remember what exactly it was)

I wasnt necessarily euphoric, though that is another symtom.
Heres the symptoms and the percentages of case study patients and what they experienced.
Symptoms Associated with Serotonin Syndrome

Mental status changes
Confusion (51%)
Agitation (34%)
Hypomania (21%)
Anxiety (15%)
Coma (29%)

Cardiovascular
Sinus tachycardia (36%)
Hypertension (35%)
Hypotension (15%)

Gastrointestinal
Nausea (23%)
Diarrhea (8%)
Abdominal pain (4%)
Salivation (2%)

References 2, 4

Motor Abnormalities
Myoclonus (58%)
Hyperreflexia (52%)
Muscle rigidity (51%)
Restlessness (48%)
Tremor (43%)
Ataxia/incoordination (40%)
Shivering (26%)
Nystagmus (15%)
Seizures (12%)

Other
Diaphoresis (45%)
Unreactive pupils (20%)
Tachypnea (26%)
Hyperpyrexia (45%