I found the following sentence in which один occurs in a plural form and in conjunction with a plural noun. I had to deduce that it is being used in a non-numerical way, perhaps with a meaning like only.
От них у меня одни неприятности.
That being the case, is this considered an adverb or a particle?
Also, is it on the level of только or всего, and if so, does it bear the same sentential stress that these words would in a similar sentence? Or does it bear a secondary stress like a number would?