Minute of Shame: My Biggest Poker Mistake Ever 🀧

Resorts Worls Manila, NL200, 9-handed

Just like all my stories start, I almost doubled my starting stack of 100big blinds, running hot. There is an under the gun limper, I make it 4x with 7♠️7♣️, a player behind me, pro-looking Romanian guy, who has me covered, calls, the limper with a 30smth bb remaining stack calls (these short stacks are common at the NL200 tables of Manila).

Flop comes K♦️9♥️6♠️, limper checks, I decide it is a good idea to c-bet small and see what happens. After both a player behind me and an limper call my 4bb bet, I realize the idea was not so good. 
This is generally not a great flop for C-betting into two people, because too many hands will continue: a king, a nine, pocket tens, 78, JQ type of hand and other gutshots with a backdoor flush draw. I don’t have the button, but have a monster stack left to act behind me instead.

I think that I am done with this hand, when I see a 7♥️ on the turn. I do not even manage to start thinking of Vegas and fucking Mirage, because the UTG guy In insta shoves for the pot-size of 27 big blinds.
Now that is weird. I expect this guy to check-raise the flop if he smashes it, so what he is saying right now, is that the 7♥️ somehow helped him. If I have two sevens myself, he is less likely to have made two pair on the turn. Did he actually call the flop with a gutshot? Whatever it is, there is a lot of worse hands that he might be jamming with, even J♥️10♥️, maybe even K9 or a set of sixes, that he slowplayed on the flop. Pocket nines would be terrible for me. If he happens have a straight, I have outs to hit my boat. 

I have a decision between calling or raising, but that will make the Romanian only continue with the hands that have me crushed. He is not supposed to have a lot of them because he only called on the flop.
So I call and things get really ugly: it’s the Romanian, who raises and makes it 70-smth big blinds more. 

Looking back, in the sound mind, such raise from a decent playeris rarely a draw, because the UTG is already all-in. Even if the button gets me off the hand, he will still have to hit on the river to win the pot. It would be better for him to overcall with a draw and keep me in the hand to try to get more value if he gets there. He is on a big stack and was capable of calling me with a gutshot. 
This type of opponent has me crushed 99% of the time.

SO WHAT SHOULD I DO?
❌COLD-CALL?
If I am beat, I still have outs, but it would take me almost half of the remaining stack to see the river. The pot is 78 big blinds and I am not getting the right price. Someone might end up hitting a better boat if the board pairs, and if the Romanian guy has a straight, he was likely to find a fold, so I was not having the good pot odds or the implied odds to justify the call. 

In the back of my mind I was thinking that if he somehow went crazy with a draw, he will shove any river, whether he hits or misses. What do I do if a heart comes? Try to represent a flush - when any of the two guys might actually have a flush? Bad idea. What do I do if a ten, Jack, Queen or eight comes? What do I do if the river is a blank?
For all those reasons I thought that calling and leaving myself less than hundred big blinds in a 240bb pot was terrible and I should take one last decision right here, on the turn: either fold or gamble and shove. 

✅ FOLD?
I only put 35 big blinds in a pot. I have every reason to think I am beat by the guy, who raised behind me. I might be also beat by UTG. If so, I am not getting the right pot odds or implied odds to call. If somebody has a bigger set, I have only 1 out to win the main pot. Clearly, folding was the best decision, and if the Romanian guy made a play, let him have my 35 bigs - if he hits the river, of course. 

🎰 SHOVE?
I still think that shoving is a better play here than folding. If my opponent has a straight, he will not be able to get away from it if the board pairs.
Me, in turn, not have to play the guessing game on the river, whether it’s a blank or the board gets worse. 

RESULT
I end up closing my eyes and getting it in. I open my eyes just to see that I was snapped by 10♣️8♣️ for a straight and the bloody guy on the UTG shows 8♥️5♥️ for a lower straight. Yes, they both called the flop with a gutshot and a backdoor. 
Sending lots of love to the UTG, who actually called two people with the shortstack and a sucker gutshot. Poker needs you. 
River is a brick. Service! Sick bag, please!

CONCLUSION 
My first problem was C-betting that board, sandwiched between the two opponents. 
My second problem was not being able to fold on the turn, because:
When there is a jam, a cold-call and a raise behind, the raiser very rarely has a draw (unless he is a complete maniac) for a simple reason that even if he squeezes the caller out of the pot, he is not able to win the bank right away, because the first player is already all-in. 

I had a usual post-hand chat with my Romanian opponent. True or false it may be, he said he used to have bluffs in this spot but nobody ever folded and used to get stacked in my spot because he did not fold a set either, thinking “Did they really call me with a gutshot?”
I ended up standing from the table even but sick in the stomach.