So, I am still playing 9x9 almost exclusively, and learning a lot from each game. As an change of pace, to see how the tactics translated, I started a 13x13 game. I won, but incredibly narrowly and only after a counting near-debacle.

was a 3-3 invasion based on the idea that 13x13 games don't really weight towards the middle, so if I could exchange territory for influence about now, that would be good.
at

my opponent deviated from the 19x19 joseki order (I only know one joseki

), possibly thinking the same thing. But that seemed OK, an opportunity to keep taking territory and put pressure on his stone on the left side. Both of those ideas worked out.
I think

was a mistake - his resulting massive central wall was nearly the death of me later on. [edit: on reflection I think I was committed at this point and had to save the two stones underneath - am I right?]
The exchanges on the right side, I think I was trying too hard to create chaos and win little fights, and not hard enough to think about eye space. When the fighting went against me (I think

was the worst blunder), it started to spiral out of control.
Around

, I realised that I might still have enough of a lead to sacrifice the stranded stones at the top. I tried to play as though I was trying to pull them out, but actually securing the bottom of the board. My count had me comfortably in front,
but I had forgotten about the five stones he had captured.
In the end it worked out, but what a squeaker. I think

(instead of

) might have won it for White, though I had the count in my head and would maybe have passed instead of

, hoping that he didn't then try and invade.
Any advice I can get at this point is gold dust!