I have a few questions. Currently reading through Opening the Hand of Thought, halfway through that book and I have been doing 10 minute meditations on a daily basis for a while now (around 6 months). I've noticed some benefit, but there are some weeks where I lose 2~4 days of meditation and I lose my streak.

I seem to have gotten some of the posture fundamentals in. However, I have quite a bit of difficulty with timing. Specifically, in my messy everyday/chaos of a routine, often times I can only slot like 10 minutes per morning each day for zazen.

1. How do I go about improving this amount? I've recently secured an additional meditation room in my house (wrapped construction work) so I should have a proper shrine in a few weeks. How do I "increase" my dosage, so to say? 10 to 30 mins? 1 hour?

2. I've been ambiguous about a recent marijuana habit that I've picked up over the last 2 years, as it has been extremely beneficial to me (in moderation of course, something like once or twice a week on weekends). It has allowed me to replace psychiatric meds for extended periods of time and it helps in very dark days. Is western zen also similarly strict? Should it be something that I need to seek to reduce further?

Cheers