re: CDC alters MMR/Autism Study?? Is this a credible source?

My son, while not diagnosed, probably falls on the autism spectrum. He was a perfectly develping child, had about 10-15 consistent words and hit every major milestone by the time he was 18 months old. He got really sick and regressed to not speaking at all, now 3, and had some other things like poor eye contact and bad play skills that set in, those have improved though not his speach. This happened 2 weeks before he was supposed to get the MMR vaccine. He still hasn't had the shot but not for the autism reason, just hadn't gotten a chance. It's a very tough pill to swallow and many try to find something to blame. MMR is given right around the time where regression typically occurs. I think it's a coincidence personally.