Something terrible is gonna happen to me?

Lately I just keep having a vague feeling that something very terrible is gonna happen to me,and it maybe even results in death or severely handicapped.I don't know what it is but it could happen at any moment.I can't help but feel that there's something big coming closer and closer everyday and it's very bad,like death of a family member or of myself.Maybe I got this feeling from the death of my cousin (he died from a stoke a few weeks ago ) and it's growing stronger and stronger,I'm afraid that I can't live past 20.Please help me,tell me what going on.