Nikon d7000 settings?

I just got my new nikon d7000 and when i shoot in manual the shutter speed is not as fast/regular like when shotting in auto or u1 or u2/ for example in an indoor shot my shutter speed is at 80, iso at 100 and at 2.8 is like if shoot at shutter speed of 1/15 i hear the aperture when it opens so slow,
how can i fix this problem? Or it is a factory problem? Even when i change the settings for faster shutter speed like 250 still is the same
all answers will be appreciated

I think you need to work a bit harder on getting to grips with the basics. But, it's possible something is wrong, post a few pictures on flickr so we can look

Well ya… That's how these cameras work - but I'll bet you didn't know anything about them before you bought did you.

Get some training, perhaps a short course in photography, read a lot, practice a lot and get some basic knowledge before you come here showing us that you don't know anything about this camera.