Well... I have to tell you that, based on my experience, it seems to me you may be playing with fire as the saying goes. I've made two previous attempts of this sort. Neither of them were planned. And I wasn't particularly depressed either (at least not any more than usual.) I don't even think I knew it was coming. I just woke up each of the two mornings in question. I was angry (at myself & the world.) So I suddenly decided I was going to do something about it. And since I had enough pills stored up, I had the means to do it.

Of course, what mental health professionals always say is: if you feel you may be in danger call someone. But what I have said to a number of the professionals I've seen is... if I was rational enough to know I needed to call someone, then I wouldn't likely be in any real danger. But if I was really in danger, it's unlikely I would be rational enough to call someone. So... given that you say you have very strong urges, my thinking would be that having access to the pills you have may be really asking for trouble. I wish you well...