DTD 50p/£1 straddles in play.
I have arrived late intent on chilling for a couple of hours on Weds night, not in a chatty or 4-bet bluffing mood, just want to have a couple of hours of cards and go home.
This is two hours in, my image is super tight. I have been ultra opportunity dead, partly due to a young lad being hyper laggy. He is on around £750, having started with £200. I recognise him and he isn't flagged up in my brain as a poor player, so he must be decent, and his play so far would suggest this, despite a couple of odd moments which I didn't quite see the sense in. For one thing he knows how to straddle properly, a very rare beast at this level.
Anyway, as I say, 2 hours in, I have

on the button. Villain double straddles for £4, as he does every time. One caller, I raise to £15 on the button, with a super tight image remember.
Villain flats, as does one other. I started the hand with £100 or as near as dammit.
Flop is

Check, check.
Obviously I expect a c-bet to get through on this board and bet £30
Villain flats pretty quickly. Even oop he feels invincible it would seem. I put him on same as me type hand, two-overs, or a small pocket pair, or maybe even complete air. A genuine hand and I reckon he re-pops me, using his image properly.
Middle player passes. Pot is now c£110
I have £55 left and given the pot size feel that the only way to win (and I should given my image) is to shove on a blankish turn which is what we get, the

Villain tanks for all of 7 seconds and calls with

So, is my line reasonable? I have played the hand with a super tight image totally consistent with an overpair.
Do I have a large enough stack to make this work (he was getting 3 to 1 to call)
Am I just levelling myself and should I accept that a lot of the time this play will work, as indeed it did against the same player about 45 minutes later?
Or, more worryingly, do I have a glaring tell? I don't normally get looked up this quick when I bluff, lol.