I need some opinions...

[pinholecam]

The real situation was much darker. It appears brighter because I overexposed it.

Thats exactly the point (not). You exposed for the overall scene which resulted in a much slower shutter speed and a very high ISO. The highlights on the t-shirt of the drummer ended up being blown.
If you exposed for the drummer only, you would get back 1 to 1.5 stops which can be used to increase shutter speed and/or decrease ISO. Not to mention subject isolation from bkgnd and less blown highlights.

Here is a PP example of your photo (let me know if you want it removed)

I adjusted the levels to simulate what if would be if you exposed for the drummer. Notice the more detailed drum area (see red arrow).
I've also cleaned up the noise a little using Paint.net's built in NR which can't even compare with good ones like NoiseNinja.
Obviously, blown details cannot be brought back, but hope you get the idea.

 

[HelloNiHao]

Thats exactly the point (not). You exposed for the overall scene which resulted in a much slower shutter speed and a very high ISO. The highlights on the t-shirt of the drummer ended up being blown.
If you exposed for the drummer only, you would get back 1 to 1.5 stops which can be used to increase shutter speed and/or decrease ISO. Not to mention subject isolation from bkgnd and less blown highlights.

Here is a PP example of your photo (let me know if you want it removed)

I adjusted the levels to simulate what if would be if you exposed for the drummer. Notice the more detailed drum area (see red arrow).
I've also cleaned up the noise a little using Paint.net's built in NR which can't even compare with good ones like NoiseNinja.
Obviously, blown details cannot be brought back, but hope you get the idea.

Wow, thanks for the long reply. Really learnt alot. Yeah I get the idea. Thanks.