I think you realize that it will do a great deal of harm to leave it in there, and I would encourage you to continue to have colonics as often as you can afford. Water and aerobic exercise of practically type will be helpful, and even walking is good.
Additionally, in your situation I don't think it's unreasonable to take a full bag saline solution enema on a daily basis until your colon is completely cleansed from rectum to cecum, which may take some time. But it's important to get all that waste matter out.