I agree with the above. Nitroglycerin only works if the problem is coronary artery disease.Make sure you've had a cardiac evaluation performed.
What kind of tablet for angina? Was the angina evaluated by stress testing, CT or Cath? What were the results of these test?
No one can possibly provide you with a reasonable answer to your question based on
the very limited information you provide.
You should be asking this question of the physician who did your testing and diagnosed your angina as well as prescribed your medications.