mouse click problem

I've got this problem for several days. Not sure about the cause.

When I click the mouse button to choose a object, sometimes (often) the first click doesn't work and I have to click for the second time to choose it. Very annoying.

Sometimes after I click and release, it seems the click keeps there and the mouse works like dragging lock. I have to click again to release the mouse.

This problem is not only applied to my mighty mouse, but also to my logitech mouse and the touch pad of my macbook pro.

I wonder if anyone has the same problem, and if anyone knows how to fix it.

Thank you very much.