Hi,
Welcome to HCM.
I have read your whole query and understand the concern.
The usual reason for this is impacted hard feces causing the clear mucus only discharge through anus during bowel movements.
The another reason can be a mass or something inside like
internal hemorrhoids which you are thinking or some intestinal worm.
So,you will need clinical examination by a Surgeon - per
rectal examination can help to find out the exact reason.
Routine blood works and stool examination for ova,
cyst and reducing substance should also be done.
However,there is no need to be worried much as this kind of problems can be managed well with appropriate treatment,so it is better to be concerned than being ignorant.
You can take antibiotics and
albendazole 400 mg as a de-worming but you will need prescription from some local doctor or GP,otherwise consult surgeon for complete treatment.
The definitive treatment will be based on the diagnosis.
Hope this helps.
Regards,