Etiquette Question

In a local stroke play tournament today. Pretty serious atmosphere, mostly single digit handicap guys, very little money on the line. More about the competition, and generally a great series of events.

All is going well, I have two guys in my group, one ends up winning at -3, the other has a rough day, but handles it well. We head to the 12th hole, very uphill par 4 playing about 255. There's a two-some on the green in front of us, reading their putts. They're both visible from the tee. The other players of my group are gonna take shots at the green, but I'm not. I tee it up and hit 3 iron, bit of a hook, peels off to the left and dies in the rough at about 65 yards from the pin. As I push up the hill, the guys in front have teed off on the next and are heading down the adjacent hole and one of the guys comes by and chews me out for teeing off while he is over his ball to putt. "You don't tee off on a reachable par 4 like that if someone is in the middle of putting! I heard you hit it while I was pulling the putter back!"

I apologized immediately and everyone moved on, but once he was gone, I was a little taken aback. Nobody out here is going to hit into you, we all know what we are doing for yardage, even if etiquette might be a weak point for some (myself included sometimes).

Got on the green with a great wedge and made a birdie, but I also asked my playing partners their thoughts on the etiquette. They both just said "oh, thats just (name), he plays a little mad, talks to himself a bit. I think it was fine."

Curious to hear r/golf's thoughts. This isn't the PGA, but its somewhat serious stroke play golf. Ball landed 60 yards short of the green. Didnt yell "fore", didn't think too much about the players on the green.

Is anyone here that bothered by their surroundings? It isn't my first run-in with people about etiquette and I've been in the wrong before. I tend to just play in my own little bubble and ignore everything but the immediate target. Was I out of line here?

Thanks