Why would you want to stop it? It's good to be emotional. It means your body and mind are releasing somethings they have stored over the years. Some sort of hidden pain or anger.
In some cases you could say it's like masturbation. Some get very emotional afterwards and have a good cry. But that is not a bad thing. It is your mind releasing chemicals and hormones. And, those that do cry after they are finished, tend to feel more relaxed since they are totally relaxed now and have let go of past negativities.
I wouldn't want to stop it, it could be very beneficial to you and a sign that your chakras are opening, or one is much more open that the others which causes an imbalance.