Bad bet?????????

$1/$2 NL

Me: suited A2d in mid position

5 players including me limped PF.

Flop: 4d 3h 2h

checked to me, I bet $10, only the BB calls

Turn: rag

I bet $10 again, BB calls

River: 5h

I now bet $15 with my straight. BB calls and turns over A6 for a bigger straight! I thought I was ahead or at worse I would have to chop. Should I have slowed down betting when he kept calling or should I have bet bigger on the turn or river?

Btw...I had about $150 and villian had at least double...,maybe more.

Any comments or suggestions are welcome.

Thanks in advance!

Is bet $10? What?