I’m the same rank as you, so take my comments as mere suggestions c:
Moves (1) – (8) are a very normal opening. The only unusual thing is that traditionally Black would make the low Chinese formation with R9 immediately, and in this game he’s exchanged first in the lower left corner. This sort of non-commital exchange is a trademark of hypermodern play; I don’t think we should consider it meaningful in this position.
(9) is a bit much. According to Waltheri, even in this post-bot age the traditional Q14 response is still basically the only move. You’re not obliged to respond to (9) and can instead continue with a double approach at R14. After (10), if Black takes the 3-3 then he’ll have entered a gote joseki and you’ll still have time to make the double approach, which is probably one reason why he played (11) as the counter-pincer. He could also have remained uncommited and immediately returned to the top right.
I don’t know much about counter-pincers but OGS Joseki has information on the position at Play Go at online-go.com! | OGS. (12) looks a little passive to me, because Black can think about jumping out with E14 and – despite the 3-3 – your shape isn’t that great if you try to keep his stones separated. The attach on top is a natural move which appears in many similar situations.
Black’s (13)–(15) maneouvre was dubious, strengthening your shape. I think you could have even considered (14) E17, trying to capture the impertinent attaching stone.
(17)–(21) is pretty normal, but it does make Black wonder whether R8 would be better placed at R9 for more of a moyo system. (22) P17 is considered to make a slightly suboptimal shape, but I think the difference between the solid connection and the descent to O18 is really quite subtle and multifaceted, having to do with endgame sequences and small variations in the balance of strength on both the top and right sides. We can see that Black took this into account by playing (23) at O16, which is slightly thicker towards the right side than the more usual N15.
Black looks to have tricked you a bit in the lower left. He got more than he deserved there. I think the best way to proceed was to first make the atari exchange (28) D2 E3 and then continue with (29) B4, but the tactics aren’t all that clear. I’m not sure (32) G5 was pulling its weight; it seems to serve a number of functions but none of them well. After (38), note that although you were able to take a “turtle shell” or “double ponnuki”, you ended up with a very inefficient stone at C6. Black’s (39) was very slow, so I guess he misread the life and death.
So, where to play on (40)? I feel it’s too early to play on the top side. If you play something like J17 then Black will probably either find a way to sacrifice the F16 stones or he’ll just ignore the attack and develop the right. I also think that moves like Q10 and P9 are too early, since usually moyo reduction takes place after the corners have been discussed. My impression is that R5 is probably the best move available in the position.