Well, I can say from experience that it is not necessarily all an issue with your control. A few years back the doc put me on some crap that totally fucked up my control. Seemed like it only took a stiff breeze to set me off.

So, you might want to examine if anything in your life is chemically different that might be affecting you.

One thing that I found exceptionally helpful when i was younger was a book called "ESO, The One Hour Orgasm" It spelled out some things that probably would have taken me years to learn without some kind of guidance. After reading it, and ummm "taking the lesson in hand" for a while. I probably tripled the time it took for me to achieve orgasm, and in those times I slipped, was able to control it enough that I never fully de-tumesce so am able to continue.

Well worth checking out even if you already have good control