I think I did fuseki alright, no wonder because split fuseki is a magic fuseki . Move 50 was bad since my opponent did build influence towards his moyo, maybe P3 was better here, move 66 should have been at C9 to prevent a pincer, move 103 should have been tenuki since that group lives in my book. So let's look at move 112: how is the situation? what sould white consider to play? how to answer if black plays T18 within the next moves? I just felt it went south after this....

4 - mistake. Should be in the empty corner, or approach.
5 punishes. Black is ahead now.
8 - consider approaching the bottom left, since Black's enclosure is already reduced by the White group on top.
To 20, White is overconcentrated on top.
22 - too early for this. I would J3, maybe, or C13.

The result to 34 is nice for Black.
34 - a bit overplay.
42 - if Black plays R8, White seems stuck for a response.
48 - you should attack the weak Black group on top.

Thank you, shaddy.

Just because I played the same kind of game today, here's another one and my question is if move 36 was ok. I have this problem often: Do I answer on my side, taking huge territory, but getting my inner group under pressure or vice versa? Here I did the first and got into some kind of trouble.

Outside group is more important, generally speaking. I think 30 is the problem with this game though - I'd rather D11.

How about 34 at f14.