Numbers on my keyboard messed up.

After updating my laptop to OS X Mavericks, the numbers on my keyboard aren't working properly.

When I type the numbers, they appear with another symbol attached to it.

I'll type out the numbers below.

1 functions as the volume increase button.

2`

3§

4] Vice versa; ] gives me 4].

5[ Vice versa; [ gives me 5[ also.

6= Vice versa; when I type the equal sign, the same thing appears.

7

8

9 makes the cursor move to the beginning of the sentence I'm typing.

Plus, the arrow keys don't work as well. When I press the UP arrow, number 9 appears. RIGHT arrow makes number 8 appear. LEFT and DOWN works fine.

All the other function keys are okay as well.

Please help me out!

This is getting really annoying.