I just played this game and it was my first loss after winning the last 5 games.
This game was was so much fun and I decided to post this since i lost by only 7.5 points.

I made many mistakes I think but I'm not sure where, but something must be wrong with my games since I don't feel like I'm improving anymore.
Thanks for taking a look.
Here is the game, I was white:

Same strength, so take my comments with a grain of salt - I could just be wrong.

I guess I have a quibble with the moves 12 and 14. First, R17 is surely a nice point, but it is not the biggest move on the board - that would probably be D15 or C15. Your stones on the top right are not in danger, because they can either go into the corner or extend along the top, so the timing seems off to me. However, once you play it, black's stones on the top right come under pressure. When black doesn't strengthen these weakened stones and instead plays p3 you jump in right away at R4. The problem with this is that when black responds, he will strengthen R9 taking away the weakness around R12.

Other than that, move 72 at E6 seems to pass up the opportunity to hassle C10, perhaps with a cap. E6 doesn't work as a leaning attack because it doesn't threaten anything, so it seems just a minor land grab giving black sente to fix his problem.

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Patience, grasshopper.

I am about your strength, so you know... the salt and the grain...

54 seems to be a pass move since the white group is already alive. I would consider d11 here.

64/66: not sure but to me the peeps seem inappropriate since they just strengthen black.

72: agree with daal.

84: blocking blacks way to the center with d10 seems more profitable here

130: as your attack at 128 was ignored, it seems that pulling the attacking stone out with j18 is natural. It also threatens to leave the black group without any eye if black didnt capture g16.

176: no need to capture right now.

190: why not capture the black stone with f8?

212: not sure, but the ko at k8 seems to be a picnic ko (after b10 which reduces the black group to one eye). Maybe a stronger player can judge this better

Everything was going fine until move 14, when white developed an inexplicable case of jealousy. No matter that his upper-left corner remained unenclosed; he plunged into the deepest, darkest heart of the black forces. To this day historians are left puzzled. Did white forget that he had large developable areas of his own? And why attach to a group instead of playing one of the other 2nd or 3rd line points?

Play in big areas before small areas. I like D15, it leaves two big followups, so you're guaranteed one of them.

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That which can be destroyed by the truth should be.
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My (sadly neglected, but not forgotten) project: http://dailyjoseki.com

Thanks everyone, you are all correct and I can see where I should improve.

@daniel_the_smith: Thank you! You are absolutely right, 14 was bad and I should avoid this kind of jealousy.

Not much to add, but while I think 14 was premature, I think it was the moves after it that were bad for you.

I agree with the others that you'd have done well simply to keep building with a move like D15. But, if you do play a move like 14, then it has to be treated as a probe to find out what shape the lower right will take, clarifying the situation so that you can plan more easily. I think your mistake was to make the solid connection at Q6. What about playing atari at Q5? If he had filled in, you'd at least have given him an impaired shape; if he went for ko, then you should be happy because there are no ko threats in the opening. You would have gained a good result no matter what. After Q5 and his fill-in at R4 you could have just skipped away with P7 or thereabouts. For sure, he could capture an extra stone or two, but you'd have established a presence in the area, and you shouldn't begrudge him getting some points after being the first to develop that part of the board. Your move Q6 was heavy and invited attack.

Up to that point, I though the fuseki looked great from both sides.

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