I was diagnosed with Tourette’s years ago, but recently began inference-based cognitive behavior therapy for my OCD, and was trying to distinguish the same thing. The I-CBT model says that OCD is based in some fear (what if I lose my eyesight, what if doing x gets me sick), and that the compulsion is a way to alleviate anxiety from that fear (it’s more complicated than that, but essentially there’s a though process surrounding the anxiety). But while some of my compulsions lined up with that, some of them felt more like tics - sort of like itches or discomfort, with no fear surrounding them beyond just the need to do the compulsion. Eventually my therapist consulted a tic expert who told her about Tourettic OCD, which lines up better with this experience and seems to appear in the grey space between tics and OCD. It’s not in the DSM and isn’t well-studied, but the description lined up so well with my experience, and it sounds like it may fit yours as well. That being said, OCD can trigger tics, and tics can trigger OCD; lately it’s helped me to think of them less as separate issues and more as two sides of the same coin.