The $2/$5 tight reg who leads the flop after calling your preflop raise is not bluffing. He flopped something real and he's not interested in letting you see the turn cheap.

Why they do it

$2/$5 regs who donk lead after calling preflop have a plan. It's not a panic bet. They hit the board and they're telling you about it. Unlike recs who donk accidentally, this player is doing it on purpose.

The adjustment

Raise only with the top of your range. With one-pair hands just call and reassess the turn. With air, fold immediately. He's not going anywhere.

What it's worth

Raising a $2/$5 reg's donk lead as a bluff and getting called or re-raised is an expensive lesson. Give him credit and keep the pot manageable until you know where you stand.