numb hands from 2iu? are you sure you're pinning 2iu and not 20?
first of all are you on legit pharmaceutical grade HGH or bathtub underground HGH? my guess is that you are not using pharma grade HGH, otherwise you wouldn't be on here asking 'what does taking GH actually do?'. if this is the case, you won't see anything shooting 2iu of bullshit HGH. and even if you use legit HGH 2iu is pretty much a waste unless you're 40-50+ years old
in theory, [in decent doses] real HGH causes fat loss, improves the quality of your hair skin and nails, tightens your skin, gives you a younger appearance (if you're older), promotes cell growth. and this is all a result of HGH stimulating IGF-1 production.
i've been taking 3iu's of legit somatropin 5 times a week for the past 7 weeks about, and i can tell you that i've become way more vascular than ever before, i've been leaning out very fast, i feel more "fit". my endurance is amazing and i think my nails grow faster too. oh and best of all, i can function properly on only 5 hours of sleep at night and before starting growth i used to need at least 7 to feel rested. i just feel great overall. i wish i could up my dose to 4iu but currently i can't really afford it