T1 Bolster leveling Problem?

[pojoman61]

I have made a new WL a few days ago and have discovered everytime I level up while in a fight I lose bolster for an instant and then its reapplied but all of the health has disappeared do to now being in combat. For example: I have over 85% health, I get a kill and lvl up and then I go down to my unbolstered health and then immediately back up to my new lvl health. The problem is that my health is now like 5-10% do to the health not going back up to its prior lvl while in combat. I have max character slots and have leveled many character with bolster and don't remember this being a thing. Is it a bug or am I super forgetful?

tldr: So Iam at 85% health, am rebolstered due to leveling in combat and now I'm at 5-10% health do to bolster. bug?