It sounds to me like you're obsessing about the possibility that you're delusional or developing sz. I'm assuming you're seeing a therapist and/or a pdoc since you have a dx and medication. Maybe you could talk to them about these fears? They would have a better idea of what's going on than we would.

Have you considered a cognitive approach to treating your OCD - since the medication has been less than helpful? I hear there are some therapies available which some people find helpful.

Good luck.