Why is my phone not charging/open?

So last night I accidentally fell asleep whist watching a video on youtube and I woke up and my Lenovo k53a48 phone was dead (drained battery) which was understandable so I put it on charge before I go for some errands and when I came home it still wouldn't turn on, the charging icon thing wasn't even on the screen. I checked every thing already. I tried turning it on by holding the power button for about a minute, I tried my charger (the original one that came with the phone) on my Sister's phone and it worked perfectly fine so what I did was just let it rest for a few hours before I went to sleep, And I charged it again, woke up in the morning and it still wouldn't turn on. But whenever I push the power button the LED notification blink. What does that mean?? PLEASE HELP.