What Could This Possibly Be?

From a very young age, up to my age now (16) I have had many "deja vu" like experiences. I used to think it was nothing, but the experiences have turned into wired feelings I get when something bad is about to happen.

The night my grandmother died, I didn't know she was sick or that she was in the hospital. All of a sudden around 10:31 p.m. I began to cry because I had a feeling something was going to happen to my grandmother, that night around 11:59 she died. They called her death at midnight.

Another incident occurred the day both my best friends died in a car accident together. They died around 1:30 in the afternoon down the road from my other grandmothers house. They left school together. Before the accident around 12, 12:30 our teacher put on some music while we took a test. The song stairway to Heaven, by Led zeppelin came on and not only did I get chills, but I also got cramps (which is something I experienced before the death of my grandmother). Later on that afternoon, my family and friends told me what happened and also told me the time they died. I nearly fainted realizing that 30 minutes to an hour I was basically given a sign of the fate that awaited my friends. I realized that maybe this is probably why I was getting cramps and chills.

To end this long passage, I have and still do have experiences with supernatural things such as seeing ghost, hearing them, and dreaming of them. I do have dreams that sometimes show future events, but nothing to dramatic. Could I have some sort of ability or is this normal?