Stop what you are doing right now. You need to take a break until your erections gets back to normal and seriously reevalueate your PE approach. In PE you generally want to use low to moderate force and more time/reps, not the other way around. I'm 3 years into PE and even I don't stretch as hard as I can.
1. Forget what you do in a gym, this is different
2. Stop pulling that hard, use low or moderate force
3. Always use heat in PE
Have you read the beginners guide?
http://www.pegym.com/free-penis-enla...uide/beginners