Does High Level Of Carbon Di Oxide In Blood Levels Cause Anxiety?

Hi, my name is Anna. I have a 12 year old son who is in the Autism Spectrum and also has a mild Intellectual Disability diagnosis. He has had 2 episodes of what I think is an anxiety attack. Both times Doctors thought it was a Seizure but all tests have come back negative for Seizures. I would like to give you the latest example; Saturday Morning he woke up to the Weather Channel as always. He either looks for it on TV or looks it up on his Ipad. He came to me and was very concerned that it was going to rain the next day. (about 4 months ago we were in Denver CO and during our visit we got caught in thunderstorm and lighting) From then on he gets very anxious when the weather starts changing during the Winter. So about 1 hr later he took his bath, changed and went to lay down, covered his face with his blanket. This is unusual for him to do. I went in and took the blanket of off him. I could see in his eyes that he was very worried. His eyes looked different, not focused, sort of wondering a little to the side. sure enough I knew it was the same as the last episode we went through. Once he gets to that stage after about 10 to 15 minutes he becomes unresponsive. He feels sweaty palms, a little hot to the touch and his eyes veer to the left. He does not seem to be breathing at all. Its like he holds his breath. When we got to the ER his blood tests showed a very high level of Carbon Dioxide. So they had no choice but to intubate him again. ( this is the second time in the last 6 months) I am desperately seeking help because I have read into what the outcome of high carbon dioxide can lead to. And it is very scary. I am wondering can his anxiety be so bad that it causes him to stop breathing instead of hyperventilating? Any suggestions you can give me would be great. Thank You