villain was 29/3

Absolute/UB Cereus No-Limit Hold'em, $0.10 BB (8 handed) - Absolute/UB Cereus Converter Tool from FlopTurnRiver.com

Button ($11.56)
SB ($11.48)
BB ($18.44)
UTG ($8.75)
UTG+1 ($4.40)
Hero (MP1) ($33.06)
MP2 ($4.59)
CO ($3.85)

Preflop: Hero is MP1 with K, K
1 fold, UTG+1 bets $0.30, Hero raises to $0.90, 5 folds, UTG+1 calls $0.60

Flop: ($1.95) Q, 6, 8 (2 players)
UTG+1 checks, Hero bets $1.40, UTG+1 raises to $3.50 (All-In), Hero calls $2.10

Turn: ($8.95) 4 (2 players, 1 all-in)

River: ($8.95) Q (2 players, 1 all-in)

Total pot: $8.95 | Rake: $0.44

I have two questions
1)Was this a terrible call on the flop?
2)How large should my pf 3bet have been?
3)I always call shoves on the flop when I have TPTK or an overpair against a shortstacker. Is this -EV? Or does it depend on their stats?

Explain.

40BB stack
3 bet pot
Overpair

What don't you get?

1) That depends on the sample size. If this is a significant sample size, then someone who only raises 3% of their hands and is raising UTG has AA, KK, or QQ. If it isn't over several hundred hands, then I include AK as well. I'm still calling, but I think I have 2 outs the majority of the time.

2) I would have gone to 4x. Normally I would only do 3 in position, but here we know that this player has a very tight range. If they have AA, well, that sux, but I am not folding KK's for half a buy in. But if they have AK I want to get the money in ASAP, and I don't think this player is folding pre-flop, but AK might very well give up if they miss.

3) Depends on their stats, their chip stack, and a variety of other factors. Grouping all short stackers into one group is a huge leak. 40-80 stackers are usually recreational players. They want to have fun. Many of them play loose passive and just want to see lots of flops to hit something. Others are very aggressive and want to push people around. Others just want to create a big pot to see if they win. If you move down to 20BB, you are looking at someone who is using a short stack to create an advantage against full stacking regulars. They tend to either be shove monkeys pushing all big hands, or selectivly aggressive, pushing big hands and hands that have a plus EV expectation based on the table dynamics and player types. Then again

1. great scenario for KK, imo. Qx can do this often enough. as well as FD
2. I'd make your bet like 1.20 and see if you can't get him to shove PF since flop is gonna pretty much be a stack off situation
3. check your DB and see what kind of results you have with TPTK or OP against 40BB or less on the flop and you can tell if it's +EV or not

Standard. 3-bet a bit more to ~1.05-1.25.
This is a good flop. You are shoving ~95% of flops and c/f the rest imo. No need to make a bet size, just put him in OTF.