Dude, it is your dick that should get hard. Not your balls. It depends on various conditions like temperature, tactile sensations on balls, genetics... Stop worrying about it, because it is nothing to worry about at all!
my dick doesnt get hard neither but thats another story my problem is that my balls doesnt get hard and it hurts me during sex
https://www.menshealth.com/health/a19541585/reasons-your-balls-hurt/ Check this site, @ramigersa, it may help Good luck!
If you have refrained for a while and then go back I would think your muscles that are used are weak. Therefore just like working out after an absence, you will be sore. I’ve noticed after awhile I don’t ejj huh ejaculate as strong or with the force or distance I was used to.
I used to have this issue when I wouldn't be horny enough. It was porn addition that made me have weird needs to be very horny in the first place but it's nothing to worry about.
Stop worrying about these kinds of details. Rebooting is a crazy process that brings a lot of physical and mental changes. Just focus on getting to the end of your reboot, healing your ED, and then you can check your balls.