Why Phone wont load Reboot

My phone stopped working, I think I may have opened a hack by mistake! so I did a System Reboot by holding down volume on/off and home buttons, and now all it does is Show the Samsung Galaxy Note 4 powered by android screen for a minute buzzes twice and does that all over again! the blue LED light stays on constantly pulsing! now can't even get into the phone at all, have tried removing battery sim card etc with out any success.... not had any previous problems,

Any help or suggestion with be grateful