First, I would say that you "have a question", or possibly "have a very specific question" (if you have
a question, it will be specific by default, so I think you would need the very
if you want to stress that it is not a general question).
As a learner, I would avoid certain in this sense.
Though both suggest that something has been singled out, I would say that particular puts more emphasis on this (and thus the exclusion of other candidates).
I would say certain (in this context) means something like "specific but unidentified or unspecified", which tends to rule out its use with this. It might (particularly in a legal context?) mean that an entity could be identified; it may imply (or the reader might infer) that the exact identity of a person is deliberately left unidentified, or that a quality is difficult to identify.
Particular may also imply unspecified or unidentified, in the sense that the writer uses the word instead of specifying the entity or quality. However, it can imply something like the opposite of certain, i.e. a (carefully) selected individual whose identity – though unspecified – is important.