Dream ?? or a nightmare instead

dreams complete life , if you work hard you could actually make them happen. sometimes i feel that dreams are just our inner thoughts and desires screaming out at us when we r sleeping. sometimes i believe they r just repeated scenes of our everyday life, or sometimes just random thoughts combined.. that's why sometimes dreams are just weird :-P

 but what about those nightmares ? what triggers them? what makes a person have a nightmare? inner fears ? negative thoughts? horror movies?? to be honest it has been a while since i had a nightmare... but i had one many hears ago and it still haunts me ..

I think I was seven years old at the time.. my nightmare started as a cute dream before it took a wrong turn, 

so it starts out with me in the park with my mom and sisters running around riding my bicycle , having fun in the fresh air, and then i find my self in front of a little grocery store and i go in to get some snacks i have always had a sweet tooth , so the man working there hands me my things and as I'm about to walk out he blocks my way i scream for him to let me go and i could see my mom waiting for me outside from the store's window but she couldn't hear me , and before i know it the man lifts me up in the air takes out a knife from his pocket and just as he is about to stab me in my stomach I wake up scared out of my mind and out of breath ....

so was that my inner fears talking to me? who knows ,,,, what ever it is it was a reminder to be careful and never go to places that might have potential psycho men that like to kill kids alone...