help settle debate on timing tells

[g-p]

ok so this hand just happened and was talking about it with someone

No-Limit Hold'em, $10 BB (2 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

Hero ($2301.91)
Button ($2225)

Preflop: Hero is BB with 9[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/spade.gif[/img].
<font color="#CC3333">Button raises to $35</font>, <font color="#CC3333">Hero raises to $120</font>, Button calls $85.

Flop: ($240) K[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/club.gif[/img], 7[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $200</font>, Button calls $200.

Turn: ($640) J[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $520</font>, Button calls $520.

River: ($1680) 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets 1461.91 </font>

they thought a while before calling turn. i pushed because i figured this mean they didnt really like their hand (like maybe they had 68 and were counting odds?). on the other hand, when a bet is on someone people usually say the person is weighing his options of calling vs raising, which would mean the person probably has a strong hand, i would think.

the opponent wasn't spectacular or anything, so no idea if he is trying to level me with time use.

any thoughts on bluffing by using timing tells?? ty