Hi
Do you mean the left and right click buttons? The fact both have failed suggest either a driver issue or the cable from the trackpad to the motherboard (which is quite easy to replace if you're handy with jewellers screwdrivers and tweezers).
Use CTRL-ESC to open the start menu then cursors keys to highlight "Computer" or "My Computer", depending on Windows version. Press SHIFT-F10 (equivalent of right click) then select "Manage". Use the cursor keys to select "Device Manager" then TAB to get to the list of devices. Select "Mice and other pointing devices", select the trackpad (or any HID device) and SHIFT-F10 to uninstall. User cursor keys to navigate up to the computer at the root of the device tree. SHIFT-F10 again and select "Scan for hardware changes".
Of course, if you've plugged in a mouse, just click your way through the above :-)
If this doesn't do the trick, I would suspect a failure of the trackpad or the cable. The cable might just be loose and a little tender shove may reseat it.
Please report back.
Good luck.