Strange. You suffer a fall and nothing happens. I, on the other hand, was coming out of the bathroom a couple of days ago and lightly bumped my elbow on the door frame. I immediately got the vibration alert saying something like “it looks like you’ve had a hard fall”. I had to cancel the emergency call and tell the watch that I didn’t fall.Earlier this week I briefly fainted in the office and fell to the floor. I instantly got up after falling however i noticed my Apple Watch Series 4 SBSS did not detect the fall.
Glad it worked out and wasn't too serious.I did have it on when I recently went mountain biking.
I did take a tumble,and sure enough the fall detection worked perfectly.
Luckily it wasn’t a big crash and I quickly disabled the sos call.