As far as the diagnostic criteria is concerned they aren't separate disorders, however its a spectrum so there is different severities. Now if functioning lables actually where about how one functioned I'd say my aspergers/autism would make me about mid functioning add the other mental conditions i have and I wouldn't even say I function to a medium level.

I have pretty noticeable sensory issues made worse by the PTSD I also have which really sucks. But yeah got diagnosed with 'aspergers' now its all autism according to the DSM so IDK seems likely it could very well just be different severiteis of the same sort of condition.