Re: peace keeper ...

Peacekeeper is getting a balanced adjustment on December 3rd, 2019 which is the next Patch Update. 

Peacekeeper cannot one shot anyone with Blue Armor anymore though since the headshot is 143. You must have been had white armor or was already hurt. Low Profile will take 150 headshot damage if all pellets hit them in the head with no helmet. 

Anyway, PK is hopefully getting nerfed correctly next week. 

Edit: you said it yourself that you weren't fully healed. I assume you had like 138 Health because you said you were 100% white and 50% blue armor. We are talking about 138 HP here and PK headshot is currently 143 damage.