Hello, thank you for asking the question.
The stammering problem at a young age is not uncommon. Alprazolam may help with the anxiety and panic attack, but its best to choose a psychiatrist or medical specialist and have yourself assessed and do follow up visits so your condition can be properly treated and medications can be reviewed or stopped when appropriate. Please note, always take a professional help and avoid trying using medications on yourself without doctor’s help. 
Best Regards.