To cont. bet, or not to cont bet? 11r Stars 45k

[Crispy]

Approaching the bubble, and of course the table is getting a little tight. Been getting a little impatient, avg stack is 50k, i have 41, blinds are 1000/2000 with antes of 75.

I pick up KJo UTG+2 i make it 5000, which has been a big enough raise to pick up the blinds. Get one caller by a sorta large stack, he has 70k.

Flop
Ac8c7s
Hero checks, Villan Checks,

Turn 7d Hero bets 11k, Villan calls 11k.

River is Kings. Hero Checks, Villan pushes, Hero Calls.

On the river I thought I might be ahead, since he didnt bet out on the flop, which would suggest he didnt have the A and wasnt protecting it from a club draw. On the river I thought it was possible he had an Underpair or missed club draw and called. I would like to get advice on all streets is possible, but more importantly, i think everything revolves around the flop, should I have bet it?

I know checking looks really suspicious, but how supicious is it since the clubs are there. Thanks for the help.