The camera "body" is fine. This is an issue with how fast your camera can collect light.
We can be more specific if you also include the settings you used when you took the shot. The camera will embed the data in the image as "EXIF" data (it's not visible but we can read it using browser plug-ins). Your images have had their EXIF data stripped (a lot of editors will commonly strip it or at least offer to strip it out. When posting to a photography website it's best to leave it in because we can tell a lot about how you took the photo and what you could have done instead if we can see that info.)
I see from your profile that you own a D3100 and you've mentioned that you were using the 55-300mm f/4-5.6 lens.
The "problem" with most school indoor sports is that the gymnasium is not particularly well lit (it's not like playing outdoors on a bright day).
The "f/4-5.6" spec in the lens is the widest focal ratio it is capable of using. The fact that it's a range (f/4 through f/5.6) means that your lens has a variable focal ratio. At the 55mm end it can do f/4, but at the 300mm end it can only do f/5.6. This is where it's important to understand how focal ratios work.
The focal ratio is the ratio of the lens aperture divided into the lens effective focal length. If your effective aperture is a 14mm wide hole and the lens' focal length is 55mm long then you have f/4. Now imagine... if the aperture was actually 28mm wide instead of 14mm wide.... your lens would then be f/2, but more importantly, at that larger size the lens could collect FOUR TIMES more light while the shutter is open for the same amount of time. What that means to you is that you could either reduce the ISO setting (for less noisy images) or you could increase the shutter speed, or a little of both. And that's just at f/4. More than likely you're zoomed in a bit and your lens' widest aperture is f/5.6. f/4 collects twice as much light as compared to f/5.6. That means that if you compared it to an f/2 lens, the difference would be EIGHT TIMES as much light... and that's a HUGE difference.
There are some zoom lenses that can provide constant focal ratios -- they don't vary when you zoom. Some of them provide f/4 all the way through the range and those lenses are a bit more expensive. Some of them can provide f/2.8 all the way through the range and those lenses are a LOT more expensive (they're also much bigger and heavier... they have to be because the physical diameter has to be much larger in order to create that larger aperture and THAT means all the glass elements inside the lens also have to be bigger and more precisely ground and shaped. That's why f/2.8 zooms cost so much.
HOWEVER... there are some lower cost alternatives.
Lenses that don't zoom at all (aka "prime" lenses) almost always have lower focal ratios to begin with. Nikon, for example, makes an AF-S 50mm f/1.8 lens and also an AF-S 50mm f/1.4 lens. The 1.4 is a better lens, but ignore that for the moment... you wont shoot below f/2 because if you do the depth of field will get so narrow that one person will be focused and the rest of them will be out of focus. So there is a practical limit to how low you can go with the f-stop even if the lens can go lower.
Since you have a D3100 (which doesn't have an in-body focus motor) you'll want to get Nikon's "AF-S" lenses (which have a built-in focus motor in the lens.)
Also, don't forget to change your focus mode to "AF-C" (Nikon's auto-focus "continuous" mode) otherwise the camera will lock focus when you half-press the shutter and they'll have moved by the time you actually take the shot. The "continuous" mode tells the camera that you're shooting a moving subject and that it should never stop focusing until you've taken the shot.
The yellow/green cast is easily removed. That's just a while balance problem. If you shoot in JPEG, change the white balance setting on the camera. This looks to be yellowish and greenish to me. Green is usually caused by florescent lights. Yellow is usually incandescent. These are probably mercury or sodium lights in the gym. Your camera wont actually have a setting for sodium lights but you can use "custom white balance". This requires that you shoot a photo of a neutral gray card (neutral gray cards are CHEAP -- get one and throw it in your bag). You shoot a single photo of the card (MUST be in the SAME light conditions as your subject) and then tell the camera to perform custom white balance based on that shot (the card should mostly fill the frame). The camera knows the card is supposed to be neutral gray but will actually appear tinted because of the lights. It'll figure out how much it needs to adjust color to make the card gray again and will then apply that same change to every shot you take until you change white balance modes again. Also... if you happen to know the color temperature of the lights in degrees kelvin you can enter the value directly (I don't happen to know the value off the top of my head.) But I'm not entirely sure these are sodium lights... that's my guess. Before you look up the temperature and enter it, you'd have to KNOW what type of lighting they use.
You can also fix the color temperature in post processing on your computer. The best way to do this is, again... take a photo of a known true neutral white or gray source. You can then have the computer perform the color correction (it'll adjust color until the known white or gray source has equal amounts of red, green, and blue balance to create a true neutral gray). You can then copy that same color adjustment to all other images shot in the same lighting.