First do a hard reset, remove the battery (if not built in) and AC adapter then press and hold the power button for 20 seconds. Plug just the AC adapter in and try to boot it up. If it doesn't boot up normally try and load the laptop into Safe Mode. From a shut down, turn it back on and keep tapping on F8 until you see Advance Boot Options then select Safe Mode and press Enter. If it still don't load to the desktop you may need to reformat the laptop to it's Factory settings using a Recovery disc that normally is shipped with your laptop or you can get them from Lenovo.
In case you have important data stored on the drive, it may be a good idea to access it with some data recovery tool for DOS mode.
After that, you can try what Laptop_Nerd Suggested. As there is a possibility that there is something wrong with the HDD, testing it with some brand specific(or third party one) testing tool would be nice.