PIED Question!?!?

Hi,
I am 19 years old I have been on my journey for about 5 months in total. During this 5 months I have not watched porn once as I realized it could inhibit me from having real life intimacy. Before the start of my journey I had no way to achieve an erection besides porn. Currently, I can get an erection without any fantasizing/porn and only sensation. I have masturbated 4 times over the past month only to sensation. The only problem is I feel like my erections are not the same as they were during porn. Is this normal? For example, I can maintain a decent erection while standing but as soon as I lay on my back it does not stand tall and firm anymore. Did anyone else experience this? Is it just a matter of time before healing? Will NoFap help this? I will appreciate any feedback!!!