If your battery has a healthy charge, the ammeter will stay around zero. Drain the battery a bit and check - turn on your lights for a couple of minutes, then start her up. If you don't see a healthy charge with a little rev then you do have a problem.
A poor battery terminal conection can cause this symptom - happened to me a few weeks ago.
If that's not it - the recent changes you made are probably it.
The service manual describes how to check the charging system with a meter, that's the quickest time to run down the problem.
