7. Qe2 looks very strong (if he trades bishops you recapture with an attack on his b7 pawn...if he ignores the thread you capture the knight and win a pawn).
10. Nc3 saves your knight.
14. Bxc4 looks better than bxc4 as it develops your bishop while avoiding doubled pawns.
16. dxe5 wins you a pawn (and possibly a bishop if he blundered and recaptured the pawn with the queen). Qd3 in that position was a blunder that your opponent did not capitalize on due to 16...e4, forking your knight and queen.
18. Qxd4 is stronger than exd4 as it threatens his bishop.
Then, you just blundered away pieces by unnecessarily moving your queen to e3 and then f4. Up until that point, the game was pretty even.
Hello!
I finished a game a few days ago, and I lost, so please tell me what went wrong. Thanks!