Problem with the quality of DSLR pictures

[nadia_88]

I took both pictures in very dim light conditions.

If there was a problem with the metering..is there any way to fix it?
How can I improve the exposure of pictures in not so great lighting conditions?

 

[nadia_88]

In addition, I think the pictures I take lack sharpness/clarity. Not including the flower picture (because I didn't really focus it)..I thought that the other picture would come out sharp. The only way I know of focusing is through the AF points.

What are some other ways to make the pictures sharper (aside from post-processing)?