I actually recommend not playing ironman on your first playthrough, the game is pretty brutal if you aren't familiar with how shit works.
Generally how 1.0 works is you can basically avoid all damage if you are skilled enough (which means there's no bullshit, just challenge). 2.0 is harder to avoid damage but healing is much, much cheaper so you'll end up doing fine anyway if you have the damage avoidance skills. Sometimes though you'll have a mimic slide up on you and fill you with a couple of bursts of 9x39 and you just fall over. Such is life; try not to let it flank you next time.