In addition to seeking medical help, I think you need to categorize your doubts whether they relate to matters of belief or some application matters. If it’s the former then know that you or I are not required to have an absolute belief, instead reasonable assurance (more likely than not) is enough for us Muslims. And we have enough evidence to have this kind of belief.
Please also refer to the videos of Ghamidi Sahab in the following thread:
Discussion 48007
If it’s the latter, then this is something by nature bound to have differing views and conflicting views at times. It is not something to be alarmed when one sees differences in applications, since they are human understanding of a matter and is by nature bound to have different applications.
If such doubts do occur, then mere occurrence of these doubts do not make one sinful, instead one should ignore them altogether, specially if they are persistent and have no ground to begin with. There is no such thing as ‘zannay ghalib‘ of a doubt, you can ignore them without categorizing them as ‘zannay ghalib‘ or otherwise. But if some genuine questions on religion arise which require academic response, then you should seek answers, in this forum and in other forums as well.
Following thread contains some useful information and videos on this issue of OCD related to religious matters:
Discussion 5479