I'd call because your big flop on a dry board means weakeness more than strengthness to some people.
Also if you think the betsizing means that much strength, it's reasonable for villain to call one of the 2 hands you're putting him on instead of raising them.

Of course we're bluffcatching, but this is 50NL, I don't give the big bets that much credit and I'd like to randomize bluffcatching based on handstrength so this one I'd call.