Wanking shouldn’t be much problems, even it is recommended to minimize it at least at begining of your journey. How long have you been doing JP90’s before you got erection problems ?
Consider doing Newbie routine or Linear Newbie routine, if you are taking PE seriously, you need to accept it as part of your life, what I want to say is do not do this for 3 months hoping you will have some results, do it every day and do not expect nothing, that way you will get much more. My point is, take it really easy and slowly. Gains will come, but this is a long process indeed and there is no shortcuts.
As for the exercises itself, number one rule is that there must not be pain, at all. If you feel any pain or discomfort it means you are not doing it right and will most likely end up like first time (or even worse). As the time goes, your routine will get longer, more intensive, more demanding but you need to get there slowly, gains will follow.
Stretching: do not pull, hold your penis at elongated state, that is all, intensity is not important as the time spent under stretch.
Jelqing: no need to squezze the hell out of your penis, have a firm but comfortable grip just as strong to push your blood up your shaft, it needs to be comfotrable and enjoyable.
I hope these hints will help you a bit, but you need to see it for yourself and understand it, just keep these things in my mind and you will master pe over time.
Starting stats 16.11.2017. BPEL: 15.5 cm 6.1 In MEG: 14.8 cm 5.8 In