I won by accidental checkmate

[I'm playing black] Well, first of all is 600 ELO so feel free to play Baka Mitai in the background but take a look around move 19. I stupidly put my rook to the only open file without realizing i aligned it in the same diagonal as my knight and therefore both pieces would be under attack, on move 20 i decided to at least protect the knight and make an even trade but he decided to take my pawn on e5 and since the position aligns well to attack the bishop and my knight is blocking the file then i decided to double attack but he just moved to d6 and on my next move since the pawn on e4 was totally unprotected and i didnt had risk of being checkmated i decided to take it and... checkmate? Oh, i see my sniper bishop that i forgot long ago is helping me and the white king is blocked by his pieces lol