Laptop won't boot up

Hi, I have a problem with my Acer Aspire V5-561

Lately I'm having a lot of trouble getting it to start. I am thinking HDD problem but please let me know if you have another idea of what it might be. Here goes the story:

- Laptop was working fine all day. Close it and go back home. When I arrive home i push the power button. Everything starts: LED for power, battery and HDD start but after a few seconds HDD light start to flash faintly. It stays like this for a long time before I get angry and I force shut down. I then famous unplug power and battery and press on power button for a minute. I let the laptop be for a few minutes and then try again. It opens up without a problem and use it all evening before closing it.

- The next day, same problem occurs. In the morning I try to open it but nothing happens for 20min. I force shut down and then do the same procedure: unplug power, battery and press power button. I then go to school and let the laptop home. When i come back in the evening I power up the laptop and everything works fine! I run a quick check of the HDD with a program from Acer and it tells me that it passed the test (i didn't do the extensive test). So I close it to test if it has changed and... here i am, laptop won't start.

TLDR: Laptop seems to only start after I unplug power and battery and press the power button for a minute. If i close it again, it won't work (LED power+battery is fine but HDD flashes). Thinking HDD problem.