Warlords Bloodlust

I had an experience where I think Warlord's Bloodlust wasn't working properly. There were several points in the game where it seemed to not be working at all even though I was very low on health and for someone running warlords my healing total for the game was very low. End game i ended up buying potions to cope with it but it was very obviously not working properly when we killed elder dragon and I got no health returned for basically the entire fight aside from the regen. I know it's supposed to cap at 5% for minion kills but is dragon excluded and even at that it didn't feel like I was getting any health back from minions even.

I was trying out a 100% crit build and it just felt like it did nothing at all to get my health back.