Although prayer three times a day is what I think every Christian should aim for, there are other times when it is right and necessary to pray. These are all addressed by R.A. Torrey in his book by Harvest House Publishing entitled How to Pray. In it, he specifies the need to talk to God before a great trial. This is easier to remember to do than at some other times.
We need to remember that "we wrestle not against flesh and blood" and cannot fight life's battles in our own strength. I confess to the temptation to tackle my own problems, and when I cannot think up a solution, I will sometimes worry rather than praying. Like a stubborn two-year-old who would rather "do it myself" than ask Daddy for assistance.
Take your troubles to God. Once you have taken them to His throne we can leave them there.