Comments like this...

I did all this when I first got into poker a year ago, and had some run good at the casino back then. I had netted 1k in 4 sessions and started to think I was better than I was.
... makes me feel that you have the right frame of mind to succeed in poker. You have the ability to recognise your own failings, which is more than can be said about the majority of people who play poker, who blame bad beats, runbad and rigged site/casino etc.

But stuff like this...

I played 3/6 limit for awhile and then used the last of it to play in the turbo tourney. I did shitty at 3/6 limit... it was very loose, all senior citizen regs who knew each other and played every hand. It was my second time playing limit live, and in retrospect I think it was a mistake. I didn't stick to a proper tight game, and played loose because the rest of the table did.
... is just so much facepalm. What the hell are you doing playing 3/6 limit vs a bunch of old timers who know each other? Why are you playing loose in a game where you are unfamiliar with the players you face? I wouldn't touch 2nl limit online, let alone 3/6 live. It's such a different game to no limit, because implied odds are next to non existent in limit. Therefore, you need to be drawing with exactly the right pot odds, and paying very close attention to how everyone are playing their hands. I'm assuming there's more than average at showdown, so you should be seeing people hands. Are you adjusting? Do you even know how to adjust vs these kind of players? I don't, not in limit.

You're setting money on fire. You might as well play blackjack.

Study the game you intend to play. Don't just turn up at the casino and play whatever is running five minutes after you get there. Plan your night, play whatever format you're strongest at, know what games you're going to play in advance, including start times and buy ins.

And definitely do not play loose just because everyone else is.