OCD shows up as unwanted, intrusive thoughts and the urge to do something, a ritual, a check, an avoidance, to make the anxiety go away. The relief never lasts, so the cycle keeps repeating, and it can take over far more of your day than anyone else would guess.
Therapists supporting clients with OCD often use exposure and response prevention (ERP), gradually facing the fears that trigger compulsions so your brain learns the anxiety will pass on its own. It's slow, deliberate work, but it's how people build back the space OCD took from them, one exposure at a time.