After 6. j14 I felt behind and played bad. I should not have played the 7-5 pattern against Csaba. Obviously, I had no clue what I was doing.

The problem in the final position is m17 which helps to kill all attempts to go to the west below the white group: 14.h17 15.i17 16.j18 17.m19, 14.h20 15.h19, 14.h19 15.m19 16.n19 17.k18, 14.h18 15.g17 16.g20 17.i18 18.j20 19.l20 20.l21 21.j19 22.h19 23.n21 and so on.

I don't think 7-5 pattern is bad. Rather 6. j14, it is not in good relation with 4.o17. After 7.m15 black has few chances.
12.m17 is more than useless, far from 5.h15 and leaves open the bottom for 7.m15, as Mirko showed. The direction of the game is the upper middle, black should try to find a move threatening both left and right compensating white's free choice between the two sides h11 or k14.