First of all, good girl for trying to taper off the pills, if you are hyperactiveT those will make you much WORSE! No, you're not too young to have thyroid problems, did you have a blood test?That's the only way to determine it. Do you have a fast pulse, or strong heartbeat? Are you losing weight/ Always hungry? Are you nervous,are you sweating more than usual? Also shaky hands too,especially in the morning( not from any other source, like drugs or alcohol) Make sure you tell the doctor all your symptoms, so he can do the thyroid testing. It's treatable, not fatal,don't be too scared. But you need to be treated if it is.