The first thing to do is to see a therapist. You said you’ve been diagnosed, but you didn’t indicate what you did with that diagnosis. I hope you are seeing a therapist regularly. The therapist can monitor and perhaps refine the diagnosis, can reassure you and can teach you new ways to manage your anxiety and the obsessions.
I doubt you are a bad person. I do think you are suffering and you deserve help. OCD is particularly responsive to a combination of some medication with talk therapy. Most people need the combination — at least to start. If you haven’t started therapy, please ask your doctor to refer you to a clinician who specializes in OCD. If you are in therapy, I hope you sharing your thoughts and concerns honestly and completely. Your therapist only knows what you choose to share. Although your thoughts may be frightening for you to talk about, you owe it to yourself to bring them up in session so they can be dealt with.
I wish you well.