It really isn't possible to give you a good answer on this from the little information we have -- or perhaps at all.
"Throat constriction" can be a symptom of a myriad of things, from allergic reactions to angina pectoris. Some of the causes are benign (anxiety), some are not immediately dangerous (esophageal spasm) and some are life-threatening (cardiac ischemia). If you have these symptoms in any other setting at all, I would highly recommend a physician's evaluation, especially if you are middle-aged or older, a smoker, or have any other medical problems.