I'd be considered low Immo, stuck between Immo 1 and 2 with a 139rr peak (EU servers)

I'm really trying to get better and I know I have the right mindset for it, but high immortal seems to be way above my level as expected, I'm curious what people think are the big differences with Low and High Immortal/Radiant players as last night i played a full ex-radiant/current high Immo 3 lobby and got destroyed.