So, um... why so eager to approach right away? I won't say this is wrong by any means, but the situation might be a little clearer once all 4 corners are taken and give you a better result since you have a better idea what to aim for.
In the first game, as well, it seems like white is convinced he is going to lose before the fight gets started really. White is by no means in a terrible or game-ending position around move 28, and has potential to engineer some sort of attack against the central black stones.
In the last game, I think after

, black has leaned on the bottom for a bit of strength and needs to use it to keep the left side stone low, or otherwise contained. In the game, when black pushes from behind and then lets white double-hane and strengthen himself, white has a huge wall facing a wide open area of the board, and black has a group curling in on itself with potential to attack a light white stone with plenty of room to make a base. Not exactly ideal.
In addition, at move 25, I'd prefer to take the top left corner, but I won't say taking the enclosure is wrong. However, when white plays in the bottom right corner, it makes the right side really big. Giving white the opportunity to play first there hurts when it's also a big point for black and white has the wall from the bottom left making it difficult for black to get much going there. As you noted, black gets a group that's basically sealed in and has about 5 points, while white's moyo is now mostly territory and white has no weak groups. After white's pressured the left side a bit, white just needs to play casual and keep things simple to cruise to victory.
That said, it's tough to fight against not only stronger players, but also the mental expectation of being slaughtered. The reward is that they point out your mistakes quite clearly, letting you know when you needed to fight back more fiercely, or that you played an overplay here, or that your judgement of the size of moves was wrong in this position. All things that help make you stronger.