Do you need both an obsession and compulsion to have ocd?

No.. Ocd is an umbrella term that covers degrees of compulsive behavior, obsessive behavior, a combo of both, in mild, moderate, or severe states. There's a spectrum of all psychiatric disorder, and a professional can assess the dx, the severity. Remember that despite labeling a disorder, each person is unique, and classifying is a way of approach to rx, based on prior cases. Rx must be appropos to u.