Died to my own grenade?

Hello there! I’ll start by saying that I am very much new to ghosts of tabor and last night and one of my sessions hunting down Krtek for the very first time. I ended up dying to my own grenade. Which is super confusing because I didn’t let the spoon go. I simply pulled the pin on the grenade, lobbed one that didn’t kill Krtek and his minions. So I grabbed a second one pulled the pin held onto it for a few seconds went to peek around the door frame, and the second I raised my arm I instantly died. The grenade in question is the picture attached. From what I can tell, I was supposed to squeeze RT to release the spoon of the grenade to allow it to cook before throwing that I didn’t do that. Any advice in terms of grenade usage and how they function is greatly appreciated and to put it simply explain like I’m five!

Hello there! I’ll start by saying that I am very much new to ghosts of tabor and last night and one of my sessions hunting down Krtek for the very first time. I ended up dying to my own grenade. Which is super confusing because I didn’t let the spoon go. I simply pulled the pin on the grenade, lobbed one that didn’t kill Krtek and his minions. So I grabbed a second one pulled the pin held onto it for a few seconds went to peek around the door frame, and the second I raised my arm I instantly died. The grenade in question is the picture attached. From what I can tell, I was supposed to squeeze RT to release the spoon of the grenade to allow it to cook before throwing that I didn’t do that. Any advice in terms of grenade usage and how they function is greatly appreciated and to put it simply explain like I’m five!