If it is taking longer than you were planning on to solo, don't sweat it. Your instructor may be delaying a solo for a few hours or so just for one thing. Your safety. I've solo'd 5 students now and I promise that if you think you are nervous, the instructor is probably 10 times more nervous.

Now if you genuinely feel that he may be ripping you off and just dragging his feet for hours that you are paying for then I'd say something. But for now just do your best and the day will come when it is supposed to come.