I guess your pdoc plays it fast and loose with the stimulants, seeing as you're now on two. Doesn't seem safe to me but I'm not a doctor so it might be. But as others have said taking a double dose means you're going to run out even faster, and your doc may not be willing to prescribe you more after that. Especially a stimulant, which can be addicting. And honestly if you take that much and then suddenly have to stop because your pdoc isn't getting back to you or doesn't approve of you taking more, you may go into withdrawal and feel even worse than before.

I'm not saying I haven't done it because I have. But it didn't end well for me and looking back it wasn't a good idea.