Worried, help! How long does flatline last?

Hi guys! I am completely new on NoFap, and I am on my 20th day of hard mode for 90 days (ideally normal if I happen to have sex) and after two weeks of being quite energetic and with urges, I found myself in a bit of a low energy state, almost no erections within the last days, and a lot of procrastination, and a little tired too. Am I in a flatline? If so, I have lots of questions regarding it. Since I started NoFap to end PM to start engaging with real women and deal with my approach anxiety and low self confidence, I am so scared that the flatline moments would extend for long periods of time (I read about guys who had months or even years of all flatline).
So, do you know how much time do flatlines last?
How often do they come?
Do they decrease or stop apprearing after 90 days or so?
I am 18 years old, and had done PMO since 12 or so (in average 1 or 2 per day).
Thank you guys and for sure I will keep going with my journey! I will listen to all opinions!

 

Thanks bro! I will take a look at it