I wonder: was it a really bad play or was i misfortunate?

I am a beginner, now playing 1,20 SNG on full-tilt. ABout 1 in 3 times "in the money", mostly 1st or 2nd.

I didn't save the hand so this is from memory:

Blinds 150/300, 4 players left

SB about 1300 chips
BB about 5500 chips
UTG 2600 chips
Button (me) with 4500 chips

I get pocket Jacks

SB was going all in with about every "reasonable" hand (A8 and up, almost any picture card with kicker 9 and up, all suited picture cards) from any position

BB solid player, but often plays out of position but willing to call an all in with subpremium hand such as AJs.

UTG loose-agressive with no respect for position

Hand:
SB posts
BB posts
UTG calls 300
I shoved my pocket jacks all in
get called by BB holding pocket kings!
Lose