If you have dreams about collisions, it generally signifies that something damaging or hurtful has happened to someone close to you in the waking life. This could be a metaphorical projection of your own issues with someone who may have wronged you or a loved one.
In your dream, the conflict from a collision often suggests a sense of vulnerability that has you feeling stuck. It might also mean the anticipation of clashes, dilemmas, or struggles with your coworkers and others.