I've been on the Depo-Provera shot for over a year and never get a period. I have pregnancy symptoms but no period to base it on. How do I know?

Check pregnancy test. Depoprovera failures are very rare. It is a very effective method. If you are concerned then take a simple test available at any pharmacy. No reason to stress out. Check a test and you will have your answer in minutes. It is normal to not have a period while on depo.