Pls help me!

I am really scared. I just want to know if nofap solves my problem. So i was masturbating at least 2 times a day( starting from today i want to stop doing it.), i am 16 btw. 2 months ago i experienced something that freaked me out. My erection was not as hard as it used to be. It used to be so hard that was starting to hurt, but now is so weak. I want to be normal again, so please answer this questions.
1. While rebooting, can i have sex if my penis is hard enough to do?
2. After rebooting and erection come back as it used to be, can i masturbate or should i quit? (If i will masturbate after recover, i will do it without porn, is it ok?)
3. When i am recovering, can I still go out with girls?
4. And the last one. Do you think that nofap will solve my problem?
Ty for your patience and for answers!