AM1 erection duration

Hello, i’ve pretty much started my journey today in hopes of unlocking my maximum boner (aswell as hopefully size gain). When doing burst expansion i can only stay hard for 10-20 seconds before going hard flaccid, even less during pyramid rush.

Im wondering if i should be expecting this or if it’s not normal, also if masturbation to get hard, sometimes nearing ejaculation, if its bad for AM1? If yes, how do u guys get hard?