I would suggest you write your dreams down as soon as you can, then figure out if there is something in yuour daily life that might be concerning you. This way you can decipher from wether its a concern or maybe foretelling. This is my method of sorting my dreams.

As far as prophetic dreams, I found out just a couple of years ago my brother has this capacity. Not that I just believed him, he started telling me stuff about me that he never knew (we lived far apart for over 20 yrs with limited communications). He is what is considered a medium.

I suggest this book:
"Do Dead People Watch You Shower" by Concetta Bertoldi

she explains how she deals with this ability from childhood onwards.