The important spring races are close at hand. As they approach, you have an undeniable need to prove your fitness. Like any addict you need just one more workout of proof to tell you that you are fit and ready to run the goal time or win the race.
Oddly enough the very act of proving fitness in training is on the short list of the surest ways to ruin your big race. Your training should be a body of evidence with some highlights that demonstrate you are in the range of your goal. Yes, hard training is necessary to accomplish anything worthwhile. But when that leads to over training or equally damaging, racing in training, it is likely to lead to breakdown before success.
Confidence is very fickle. I like to remind my runners that a great workout shows you are fit and a bad one simply shows you had a bad day. It does not mean your fitness somehow disappeared since last week.
Even better than reading your training log, running 3-5 races (maybe more for shorter distances) should also lend all the support to the viability of your goal. Again, if those races do not offer the sought after confidence then it is time to reconsider what is possible for you right now. Realize wanting a goal, no matter how deeply, does not mean you are ready or capable of doing it. At least yet!
The most successful Olympic American distance runner in history, Frank Shorter*, said that there are two kinds of workouts; those that make us fit and those that demonstrate fitness. He pointed out that if these two types get out of balance you are likely to become the fittest spectator on the course.
*Frank won gold in 1972 (adding to a 5th place in the 10,000) and silver in 1976 in the marathon.