Whether you will have seizures after stopping alprazolam, is difficult to predict.
However, if you are using only one 0.25 mg tablet a day, it is less likely. There is no foolproof way to predict however.
You must still consult a psychiatrist
for your anxiety
and panic attacks. Having panic attacks during marijuana use may be an effect of the drug. However, since your anxiety has been persisting for over 2 months despite stopping the use of marijuana, it is advisable to seek professional help. You can get relieved of your symptoms with medications that have no risk of addiction.