Most has been covered by the others. Images are all too dark, but could be lightened up in post, 3rd shot is the best and could be made better with the right crop. The other 3 are weak for sports action, cutting off the hands and the ball is a delete. Always try and keep backgrounds straight, level playing surface. I'd give it all another shot, it's the only way you'll get better at it, not always an easy sport to shoot, especially with a short lens. Try shooting from the corner of the court if you can, a lot of the play comes to the corners. Bump your iso up as high as your camera can handle without the grain becoming too bad, keep the shutter speed up around 400th or higher and the lens wide open. Stopping the action is more important than having a little too much grain, there is a trade off under poor light. It's also not likely that you'll be making posters out of the images, so 5x7-8x10's would probably be acceptable, if the content is there.