Re: I am such a hookah failure.
First of all, don't be so hard on yourself. It takes time and practice to improve your skills.
I would pack your shisha down firmer and use some more. People say don't over pack the bowl, but you will know when there is too much and too tight because it is hard to draw/inhale. I believe this will improve your sessions. I also use a sewing needle or a thin metal pin to poke my holes now.
I make lots and lots of tiny holes rather than fewer big ones. The holes your size, like I used to make, let the coals ash into the bowl as you smoke. This irritates my throat and may be part of your problem.
So, as THS above me said, smaller holes, pack the shisha more. If you still have problems use less coal, but it looks like a thick bowl so the heat may be needed.