1998 Cadillac Catera Car wont start after starting fine

I was driving up a hill and stopped in traffic about 3 weeks ago and my car cut off but started right back up and drove fine. Then about a week later I drove to a store and shopped and when I came out the car would not start. It made the sound like it was about to start but it would never catch and actually start. Then after about 5 minutes it started and ran fine. I drove 5 minutes and went to another store and when I came out it started fine and I drove home perfectly. Then 2 days ago I was in the drive through and as I was making the turn to the window it cut off again. This time it wouldn't start back up right away, just making the sound but not catching. After 5 minutes it started and drove fine and I went to work. Last night I drove about 2 miles and parked and it wouldnt restart. Another 5 minutes and it started and drove fine. I know I have a bad car that is known for it's problems, but it is my first car and I really don't know anything about cars so any help would be so wonderful. Thanks.