Help with a hand

Hi everybody, this is my first post

I was just wondering if i did the right thing at a no limit tourney with two hands that ultimately made me lose my good cheap lead ( i had the biggest stack)

First hand went like this

I had JJ in dealer position, blinds 600-1200 my stack 55000
Someone raised 4x bb (2 positions before me)
I called

flop came out iwth 3 low cards with no possibilities of a straight. They were however of the same suit. However i believed my JJ was good because the better bet an amount of 4x bb pre-flop. He went all in. I knew it was a follow up bet to the preflop one and didn,t think he had the flush. His all in was about 24 k. I called and he had AK off suit but K being the same as the flush draw on the table. His suit came and he won the pot with a flush higher than mine.

Should i have played my hand differently and why? Any advice would be appreciated.

Second hand I had AQsuited

8 players left on the table.
Under the gun goes all in (I have maybe 10k more chips than her), everyone prior ot me (dealer) folds
I have 23.5k in chips
blinds are 6k
I go all in since i'm figuring i'm going against a small pocket and due to the fact that my stack is not even 4x bb.

SB calls my all in. A side pot is made for about 13 k of my chips

UDG has 77, SB has 66

Flop didnt help me and I lost against both.

Should i have done soemtihng different and why?

Thanks a lot in advance