stars 30/60, i am too safe = sorry?

[J.Brown]

Sit in the BB first hand, get the 2 Black Aces.

raised in mp, someone i have never seen.

i three bet. he calls.

flop K 5 3 rainbow.

i lead, get raised, three bet, he caps, i call.

turn J (no suits), i lead, he raises, i call (?)

river 5, i lead, he raises, i call (?)

the reason for my question this line is that it has seemed to come up quite a bit lately.

i have a big hand, most likely the best hand, i have no problems with aggression, but............

it seems as though i may be being a touch to safe in spots and not extracting the maximum.

all thoughts and comments appreciated, i know this is a fine line.

cheers. J.