Why is my car shaking? !

Long story short, I was racing a mustang earlier today in LA and when it was all set and done(of course I won) I pull up to the traffic stop and my car is shaking while I'm waiting for the light.... Light turns green, I let go of the brake before pressing gas to proceed and its more noticible. But while I drive I can't feel it at all....

Does anybody know why this happened? And what can I do? !

Would really appreciate it