What do you think about this game?

Yes the rook is pinned,
Queenxe6 is "two checks" in move 24, the check of the queen and the x-ray check of the white rook on d7, not the best explanation but I like it, after the check the black rook on e7 is attacked by 3 pieces.

Interesting idea, rook pinned I am tired but I think its correct, a rook it is like a cross in rows and columns, It is usually directed like a line or a vector, so two rooks together in front of each other * are like a magnetic force and loses its other possibility this time the vertical direction.

* and a king ( rook, rook and king)

5 Bf4 loses your central pawn e4 without any compensation
You missed 16 Qe5 with double attack on Be4 and g7
17...f6 puts his king in jeopardy. Just 17...Qe7 and black should win the endgame with his extra pawn

5.Bd3 was much better, protecting the e4 pawn and developing a piece.

5. Bf4 it's blunder, loses a central pawn and a critical tempo and gains only developemnt without target, better was Bd3.

7. Bb5?! it's intersting, you leave the oppurtinity to opponent to created you a isolated pawn with cxd4 cxd4 and also advange his a,b pawns with tempo, one of main plan in sicilian for Black, but you gain the lost tempo in the opening with an active move.

15. Nc5?? it's a blunder you lost the oppurtunity to take back your pawn and to destroy Black's O-O with Qe5.

17 Ne5?! your last mistake to equalize for the pawn by Nd4, now you give the opponent to finaly O-O or trade his Rh8+pawn for 2Knights after 17..Qe7 18. Qc7 with option either O-O or Qxc5 Qc8+

21. Rad1 seems more accurate

Bad play from both, special for Black as his was winning from move 5, your opponent didn't give much to learn, but you can try to correct your mistakes :
1) If you find a move to play, try to find one even better
2) Find the best respond for you opponent, before make your move
3) Try to be more accurate when you attacking leaving no chance to survive.
4) Don't give pawns without compesation (I'm always remember GM saying : "I become GM by winning pawns"). Give pawn only to gain tempo, create better pawn structure or activate a bishop or to place an knight in same square.
by playing the same position after each mistake against free engines like critter or komodo (more human style) at least 2 times so to understand.