Please proofread and comment on this

Hi,

This is an entry of my diary (but I used the third person) and while writing it I found myself hindered by my limited vocabulary and knowledge of different sentence structures.
Please help me proofread this and especially the last sentence, which I simply didn't know another way to write. If you find any use of words strange or if you have some stylistically better alternatives in mind, you are more than welcome to rewrite the whole sentence. I would really love to see how a native write would phrase what I wanted to say in this.

While Chris was using the computer, determined to sleep early today, he saw a cockroach against the ivory wallpaper at his home. He didn't hesitate before grabbing a mosquito racquet with which he intended to electrocute the roach. Walking closer to where the seal brown creature was, Chris gingerly reached for the sport section of today's newspaper, which really could serve no higher purpose than ensuring the roach's demise. He inched the racquet towards it before suddenly speeding up his movement in an attempt to take the roach by surprise. But with agility that could make any ballerina envious, it escaped, and before you can say Jack Robinson it had already moved dangerously close to his feet.

Chris hadn't been confident before his first strike, and now he was even less so. But his preparation wasn't wasted. He swiftly swatted the roach with the paper in his hand, but not too hard so that the roach wasn't completely squished, which avoided a disgusting scene. Its exoskeleton proved sufficient to save it from death, but not from injury. Chris pinned it to the floor with the mosquito racquet, but because the roach was too flat to be touched by the its wires, it escaped death once again. He tried sliding the racquet on the floor to force it to move, and occasionally its antennae would touch the wires and make some buzzing sounds.

After doing a lot of sliding and staring, Chris finally decided that the roach's lack of movement indicated that it had left this earthly world. But no sooner had he lifted the racquet by a mere inch did the roach started moving again. Almost as a reflex action he pushed the racquet back down, pinning the roach yet again against the floor.

After the roach resorted to artifice and almost managed to break out of this temporary prison, Chris left the racquet on the floor, the roach still beneath it, and woke his father. His father reluctantly carried on what he started. He didn't know what exactly happened, but a few minutes later the roach really was dead.

Chris tried to flush the roach down the toilet, but even when dead, the roach was a more skilful swimmer than he was and remained afloat after a few flushes. He had to turn on the shower and use it and apply the flush at the same time to finally generate enough power to flush the roach down.

Thank you very much in advance!