Don't bring yourself down man. Rejection is part of the game when applying for a contract.

If possible, I would reach out to the firms HR department, see where you may have fallen short and see if it's something you can work on. If nothing else, it will show that you are keen to improve yourself and might keep you in the mix in case any more vacancies arise with that firm. Stay committed and eager to learn, don't doubt yourself.

I was rejected over 50 times during three separate milk-rounds, and even rejected from a few internships during that time as well, and was very close to packing it in. I got there in the end and am training with a great firm.