Learn to keep stroking
Hey you should be looking at me, not my house. I know that i am rich :)
But hey did you know that you have been stroking for over 7 Minutes now? See it isn't that hard, and you thought you never could do that. I know the speed is still a problem, but you have to learn to feel comfortable to keep stroking at a slow speed first.
Apply some fresh lube again, you are going for a faster ride now, i don't want you to feel too much friction. Start increasing the speed over a minute again, like before, but after that minute i want you to stay at that speed you reached. Keep stroking at that speed for 3 Minutes.
Try to relax, don't let the arousal own you. Deep breaths, you can do it. Don't think about cumming, concentrate on keeping your arousal at bay. If you feel you are going near the edge of orgasm, back of to standby speed slowly. Cool down while stroking at standby speed. You don't have to stop completely, you have to learn to cool down with slower strokes.
If you had to back of to standby speed, apply some more lube, and try to do it again. You have to train your mind to control your arousal, don't let it rise to fast.
If you can't do the 3 Minutes at the third try, stop. Yes stop stroking, go to the shower, take a cold shower and clean yourself. Relax for 15 Minutes and then come back and start at the beginning. You are going to learn this today, one way or the other!
If you did manage to stroke for 3 Minutes without reaching an edge, you may slow down to standby speed and ...