OCD in particular and anxiety disorders in general are treatable in majority of the cases. Most common causes for improper treatment are either not being on right kind or dose of the medications/other treatments or improper diagnosis. If these two issues are properly taken care of majority of the patients with anxiety disorders can be treated.
OCD and anxiety disorders are often treated with SSRIs (Fluoxetine, Sertraline, Citalopram, Escitalopram), Venlafaxine, etc. Other medications that are used are older medications called as Tricyclic antidepressants (Clomipramine specifically for OCD), Benzodiazepines (lorazepam, Clonazepam, etc.) and in some cases a class of medication called as MAOIs (monoaminooxygenase inhibitors). In addition to medications, a type of therapy called as Cognitive Behavioural Therapy (CBT) has been shown to be very effective.
As far as the medication dosage is concerned, OCD as well as other anxiety disorders often require higher dosage of medications (in some cases as high as 100 mg of fluoxetine). I see that you are only on 20 mg of Fluoxetine. Assuming that your diagnosis is correct you may need higher dosage. The best or most effective approach is probably a combination of medications and CBT. In case of OCD a specific kind of CBT known as Response-Prevention therapy is beneficial.
I suggest that you see someone who specializes in anxiety disorders/OCD.