Hi, congrats on starting. I'm new too, but I've been reading up on the site for a few weeks now. Please don't take this as your one source of info, because I could be absolutely incorrect.
There are a few threads that are worth reading that should be able to help you out:
Breast Growing Notes - https://www.breastnexum.com/showthread.php?tid=24358
The comprehensive thread on the basic principles of what processes help aids breast growth. Use it as a guide to fill in any gaps in your regimen you should try.
The Topical Cream Protocol (by Lotus & Heavens Night) - https://www.breastnexum.com/showthread.php?tid=32098
Seems to be the most effective method of breast growth available, aside from straight up HRT. There's a lot of stuff in here, but I'd recommend pages 1 & 8 for lists and summaries.
Lara's take no shit guide to hardcore Noogling - https://www.breastnexum.com/showthread.php?tid=31273
A guide for pumping.
Please note that any program you try that works has some chance of messing with your ability to function; it's the nature of the beast. You have to accept that risk before starting. Your body has a "use it or lose it" mentality. Loss of male function happens from low androgen levels; if you want to keep male function, you're going to compromise speed and size of breast growth by keeping your androgen levels high, or you're going to need to take Cialis or Viagra regularly to keep it working. In either case, you might want to keep your doctor informed, in which case, if you're lucky, they'll probably just recommend you go on real HRT, which you should probably do.
Please also note that there's nothing you can do that will have fast results. Even real full HRT is slow. Don't expect any significant visual changes for months.
They say it's a marathon, not a race. I'd also recommend keeping an eye on your hormone and blood levels, especially since you're taking PM, since it's known to increase chances of blood clots and DVT.
Lastly, I'd recommend gaining weight if you're skinny. Tissue growth of any kind is much easier in a calorie surplus.