As noted in the comments, after 7.Qxb7??, the reply ...Bc6! simply traps the queen, leaving White completely busted. This may be the most obvious thing both players failed to notice in this game, and one of the few concrete ones I will bring up in this answer.
To me, it looks like this game is not an elite game, and it would be interesting to know your overall strength. I can assure you(without even analysing deeply), that black made more "mistakes" in this game than just missing 7...Bc6, but they may be more or less relevant depending on your level of self critisism, and ambition.
Let's take for example the position after 10.Qa6 by White: Did you consider playing ...Nb4, threatening both the queen on a6 AND a nice fork on c2? To me, not considering the move could be considered as a mistake, but at that point you already had quite a nice position, so most reasonable moves by black should be enough to win by then.
But there are other considerations to be made in the game. I think, that in this game, you did not develop your f8 bishop efficiently. This I view as a mistake, but it's not a tactical mistake, rather a positional one. But White never capitalised on this in any way, so you weren't punished for it. And this is the important point I wanted to make with this answer:
In this game, you outplayed your opponent, and the reason for it was that your opponent didn't play well enough to stop you from bullying his queen around the board. Therefore, your opponent will have a much easier time to learn from this game than you will. Your opponent got the "You play badly, and here's why"-treatment from you this game, but you didn't get the same treatment from anybody! Therefore you think you played great, no matter what the reality of your play is like.
This is the reason why it's easier to learn from your losses than from your victories in general. I would advise you to go through this game yourself with a bit more self-critisism, if you really want to take anything from it.