What is the limit of the manifest (apparent) and the hidden (inward) forms of remembrance (dhikr)? And is it obligatory to wash the meatus (urinary opening) when cleansing with water (istinja')? And is it sufficient to pour water on the penis without rubbing it when cleansing (istinja')?

You have been overwhelmed by obsessive thoughts, and they have gained great control over you. The cure for this is to ignore them and not succumb to them. You should perform istinja’ (ritual cleaning after relieving oneself) in a normal manner by pouring water over the area of impurity until you are reasonably sure it has been removed. A strong presumption is sufficient; certainty is not required. After that, do not pay attention to any obsessive thoughts that may come to you.