Venlafaxine and serotonin syndrome?

So I've been taking venlafaxine a day for over 3 years now. Venlafaxine is the only prescription I currently have. I started at 75mg and moved up to 150mg a day for a couple of years. Not long ago my doctor decided to bump me back down to 75mg since many of my original depression symptoms have disappeared. I've only recently bothered to wiki the drug and stumbled across serotonin syndrome. Does it seem like I should be concerned about serotonin syndrome at all?