yeah, the eidogo plugin doesn't support 15x15 board sizes.
and your opponent realized you're a beginner and apparently wasn't interested in completing the game
- Click Here To Show Diagram Code
[go]$$cm13 first corner died.
$$ --------------------------------
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . X . . . , . . . O . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . X , . . . , . . . , . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . 1 . . . . . . . . . . |
$$ | . 8 O O . . . . . . . . . . . |
$$ | . 7 B , O . . , . . . , . . . |
$$ | 5 . . B 2 . . . . X . O . . . |
$$ | . 3 6 4 . O . X . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ --------------------------------[/go]
after the

exchange, you played away risking losing your two marked

stones in the corner, and

and

doesn't seem to help your shape here. After

, black can certainly no longer survive in the corner or escape
- Click Here To Show Diagram Code
[go]$$cm27 what is the plan?
$$ --------------------------------
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . X . O . B . . . . . |
$$ | . . . X . . . 3 4 . . O . . . |
$$ | . . . . . . . O . . 2 . . . . |
$$ | . . . . . 5 . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . X , . . . 1 . . . , 7 . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . X . . X . . . . . . . 8 . . |
$$ | O O O O . . . . . . . 6 . . . |
$$ | . X X , O . . , . . . 0 9 . . |
$$ | X . . X O . . . . X . O . . . |
$$ | . X O O . O . X . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ --------------------------------
$$ {AR 12:6 12:9}[/go]
now,

needs some help, but you played away with


encloses the lone stone while aiming to make additional territory along the side
the wedge,

can be a trick play to gain some ground elsewhere. You see its already at a disadvantage with only two liberties in between two stones with 3 liberties each. But after

, you played away (with a move with no meaning -- doesn't defend anything, doesn't attack anything).

is a nice invasion trying to break up white's side

protects the corner, while putting pressure on your side stone

I don't see how black can possibly live in here

white says "thank you" for helping me make my corner even stronger.
- Click Here To Show Diagram Code
[go]$$cm39 lost invasion
$$ --------------------------------
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . . . . X . O . X . . . . . |
$$ | . . . X . . . X O . . O . . . |
$$ | . . . . . . . O . . O . . . . |
$$ | . . . . . X . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . . X , . . . X . . 2 , B . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . X . . X . . . . . . . O . . |
$$ | O O O O . . . . . . . O . . . |
$$ | . X X , O . . , . . . O X . . |
$$ | X . . X O . . . . X . O . . . |
$$ | . X O O . O . X . . X O . 1 . |
$$ | . . . . . . . . . . . . . . . |
$$ --------------------------------[/go]
while still futilely attacking the corner (

) instead of helping the invading stone,

, white encloses the side with
- Click Here To Show Diagram Code
[go]$$cm47 can not connect
$$ --------------------------------
$$ | . . . . 3 . . . . . . . . . . |
$$ | . . . . . . 2 1 . . . . . . . |
$$ | . . . . . X . O . X . . . . . |
$$ | . . . X . . O . O . . O . . . |
$$ | . . . . . . . O . . O . . . . |
$$ | . . . . . X . X . X . . . . . |
$$ | . . . . . . . . . O X O . . . |
$$ | . . X , . . . X . . O , X . . |
$$ | . . . . . . . . . . . . . . . |
$$ | . X . . X . . . . . . . O . . |
$$ | O O O O . . . . . . . O . . . |
$$ | . X X , O . . , . . . O X . . |
$$ | X . . X O . . . . X . O . . . |
$$ | . X O O . O . X . . X O . X . |
$$ | . . . . . . . . . . . . . . . |
$$ --------------------------------[/go]

can't connect

? The first line, is known as "the line of death". this move doesn't help you at all. it doesn't build any territory, it doesn't defend anything, it doesn't attack anything.
from here, white merely solidifies the entire right side. nothing you can do will live there.
In the end, white "owns" more than 3/4 of the board.
- Click Here To Show Diagram Code
[go]$$c game over
$$ --------------------------------
$$ | . . . . X . . . . Z . . Z . . |
$$ | . . . . . . O Z O . . Z . . . |
$$ | . . . . X X . O . Z . . O . . |
$$ | . . . X . O O . O Z . O . O . |
$$ | . . . . . . . O . O O . . Z . |
$$ | . . . . . X . X X X O . Z . . |
$$ | . . . . . . . . . O . O . O . |
$$ | . . X , . . . X . . O , Z . . |
$$ | . . . . . . . . O Z O . . Z . |
$$ | . X . . X . . . . . Z . O O . |
$$ | O O O O . . . . O . . O . . . |
$$ | . Z Z , O . . , . . . O Z . . |
$$ | Z . . Z O . . . . Z . O . . . |
$$ | . Z O O . O . Z . . Z O . Z . |
$$ | . . . . . . . . . . . . . . . |
$$ --------------------------------
$$ {LN 7:1 7:4}
$$ {LN 6:4 11:5}
$$ {LN 11:5 9:11}
$$ {LN 1:11 9:11}[/go]
Hope this helps.
Welcome to the world of go.
Good luck in your journey.