keyboard shift irregularities

i have a new toshiba satellite and lately when i push the shift key, either
one, it just changes everything. when using the keyboard everything is in
caps even though caps lock is off. i can only type special characters. if i
put caps lock on everything goes to lower case but i still can't type
numbers, comma, period etc. i can't individually select anything with my
mouse, it will highlight everything from the top to where i clicked and i
can't shut my computer down from the start menu, i have to hold down the
power button. after 'the change' when i push shift it types nb tilda a. it
doesn't spell out tilda but i can't push shift so...

i've turned of sticky keys, filter keys, shortcuts for them everything i can
think of. i took the shift key off and put it back. anyone have any ideas
as to what's going on 'questioin mark'