HU hand i think i played poorly

[Kyle]

I am the SB and I am the button. BB is very laggy but not a retard.

I open with k9o. BB three bets. I call.

FLop comes k 8 blank.

BB leads i call planning to raise turn.

Turn comes 10 BB check i bet he calls.

River comes a 9. BB checks I bet he raises I.... ????