Listen to tommybommy.
We all hope it's telogen effluvium and 99.9% of the time it isn't unfortunately. You'll only get acute Telogen Effluvium from extreme physical or psychological events for instance surgery, being hospitilised from a accident or the kind of mental breakdown that would have you admitted to a psych assessment unit.
Typical anxieties such as worrying about acne, exams or the loss of your beloved dog won't have an effect on your hair unfortunately.