Hey guys, my first post here, and im new on poker, ive been taking it seriously less than 4 months ago, having decents, results...and playing mostly MTTs, i did lost the hand with exact stack size and all that info, but id like anyone's opinion on the way that i played, also trying to be very specific , mostly to get an opinion on my thinking process, cause i believe it was correct on certain way, but i also felt a little bit fishy , but not 100% sure. Also taking in count that i play mostly tight, but having notice that you have to go for it, and explodes weaknesses on late stages of the tournament, where people is too scared of bustout.

So, it was a tourney on pokerstars. 3.30R, 25k G, and we were around 70 players left (around 3.5k players initially), Blinds on: 10k/20k , and i had a little bit more than 800k, being 8th-10th in chips on the tourney. Average around 20BB, I was playing agressive, stealing blinds on short stacks and had a little bit of a war with a guy with my same stack size i had, pulling out a big bluff where i almost double up so that gave me like maybe too much confidence. Anyway.....

A guy just arrives to my left with 1.2m chips, being like 2nd in chips on the tourney ( no read on him) and there was a guy on my right with 25bb who was raising a lot of pots but folding almost always to 3 bet preflop, and giving up on flops, without making c-bet, i had 4-3 suited on UTG+3, so the guy on my right raise like he was doing it (2.5bb) (UTG+2), i decided to call, feeling i could hit my hand and disguised it, and/or outplay him like a did couple of times before in the previous hour, and the guy on my left with the huge stack decides to 3 bet (7bb) folds around till the guy on my right and he folds( as expected) and i called, this time more cause if i hit my hand and he has a legit hand i can get a huge double up and cause i felt he being the chip leader might be stealing and applying pressure and being both of us big stacks he may not want to get in a lot of confrontation ( is that a correct approach?),

 the flop came 843 (two pair for me).. all diamonds i check, and he bets half of the pot, ( at that point i didnt feel it was air, and i put him in a big pair...or at worst at AK, AQ with aces of diamonds...) i shoved all in (effectively around almost 35bb), and he called , tabling AA ( wit the diamond ) being a flip... he hits his flush at the turn, and i got busted in 71th place. (wining 61 dollars)

So winning that pot was around 1.8 million, and he took the overwhelm chip leader...my thinking was, if i win this hand, i can still applying pressure... and have a really good chance to get to the final table, also 1st price was 5k, and i really didnt care about wining 60 or 100, or 200, i wanted to go for the whole thing, or at least the top 3 payouts,   the other "benefit" i tought playing that hand is that people would see me too agressive, and win a little bit of " fear equity", then start protecting my stack playing more solid against medium stacks and gets to the end..., so after all i felt it was worth the risk...but what do you think?, is a line too risky?, maybe is a must to fold preflop agains that 3 bet a marginal hand like 4-3s? , or it was incorrect just the call preflop n UTG-3,  even having decent odds.

Please excuse me for my lack of professionalism explaining the hand, with the details that the hand should have , also for any mistake on my english ( not my first language),

Thanks in advance for any comment. :)