I would talk to his doctors but I wouldn't worry about it too much.
How old is he? I know around Jr High my ability to self regulate went down the drain and I was an emotional roller coaster. My son is now 12 and he seems to be starting the same thing. IMO we learn a lot of ways to cope with being auti/aspi from infancy through childhood. When the hormones and stuff start changing in adolescents I think that many of the ways we used to cope no longer work... We have to re-learn how to live as an auti/aspi in an adult body. I know for me it was frustrating and depressing because I started to struggle more and more and couldn't understand why things were going down hill.
Also if there have been changes in his world recently stuff like this can happen too.