Grannie, I'll say the msjoleary is right about the good, better, best guide-lines. I personally don't recall advice of doing a lot at the beginning and then backing off. I suspect that is a defacto situation of most people starting anything.
I'll just add the note of regularity in practice. It is better to do 30 minutes once a day, everyday, rather than doing a 3 1/2 hours meditation once a week. If you can do the meditation at the same time each day that is better. But every little bit is good.
If your practice grows in duration it is by your choice to progress with your development.
You are perfection.
Iam2 
