A lot of times you'll find that other disorders are called OCD in fact when they are not.
Ruminations of depression are basically in simplistic terms when a person dwells on past mistakes and has regrets.
If they do not perform rituals to deal with this, they do not have OCD.
What's important to understand is that OCD is not a blanket disorder that should be thrown around lightly.
If someone that does not have OCD is treated with OCD relieving methods, they are most likely not going to get better because their real problem is not being treated.
Sometimes it's important to get a second opinion just to make sure that you have the correct diagnosis.
I would not recommend that you tell your doctor that you are doing this, because some of them have a god complex and will be offended and that could affect how they treat you in the future.
This is sad a but true as doctors are humans too.
So we all know that OCD is basically characterized by the fact that the sufferer has a fear, which drives anxiety which drives the person to perform rituals to deal with this anxiety and then the cycle starts over and most times immediately.
When ruminations of depression get to the point where the sufferer starts to perform rituals, then they may have ruminations of depression and OCD caused by it or something different altogether.
Take action: It's very important to get a good diagnosis to make sure that your "OCD" is in fact OCD and not something else entirely different.
Get a second opinion discretely if you have any doubts.