Are you or your child a high-functioning Autistic?

To make a story short (not really - lol), my 5 yr old was diagnosed with autism. He has a speech delay and we were getting him tested across the board when I was taken by surprise last week by this diagnosis. Not shocked - I now understand why he's so... quirky but I'm trying my best to understand this condition better so I can better help him navigate through life.

My son was born at 35 weeks after a very complicated pregnancy, I suffered from the worst case of hyperemesis gravidarum my doctors had ever seen, so keeping us both alive (with zofran and phenergan)until I delivered was the ultimate goal. Thankfully at birth, aside from low birth weight my son was otherwise healthy. He did have some GERD he outgrew eventually. One thing I did notice is how high-needs my baby was - he wanted to feed constantly and if I was not next to him he'd wake up even from a deep sleep and cry. He cried a lot as an infant. He did reach his developmental milestones a month or two after kids his age, which I chalked up to his being a preemie, but he was a late walker. Now in retrospect I realize his fine motor skills have always lagged behind. He was starting to talk normally and started walking by 14 months of age; shortly after that his speech began to regress from "mama, dada, moon, dog, cat, etc" to just babbles. I was going through a difficult time with my divorce and dealing with a difficult ex and learning how to be on my own for the first time, so I was distracted by other things. It wasn't until the nanny mentioned to me that the baby was "regressing" that a flag went off in my head and I raised the alarm at the doctor's. Thus began an endless stream of visits to specialists (ENT, speech clinics, etc) and no one could tell us what was wrong with my son, who could not speak clearly by 2 and 3 yrs old. He was enrolled in an early-intervention program where a therapist would come do therapy at home - didn't help at all. Finally we had him tested and accepted into the program for children with disabilities at our local school and he began to thrive under this structured environment. He made huge leaps and bounds and has now "graduated" from the program and will be going into regular kindergarten, which I find both exciting and terrifying.
We found him to have a submucus cleft palate which makes it hard for him to form some sounds and his diagnostic visit to the Phd resulted in the autism diagnosis.

My son speaks fine now, but some sounds are hard to understand until that cleft palate gets corrected. He is extremely intelligent and speaks a lot. He's very curious and always wants to know what's going on, hes a funny, hungry, chatty, curious 5 yr old like any other boy - I just am nervous about him being put into a regular classroom, and how this will affect his condition. He's very normal in his interactions - he's verbal, good eye contact, high curiosity, very physically active, but he has poor muscle tone and fine motor skills, he's clumsy and uncoordinated and talks nonstop and sometimes doesn't realize how he can be really "in your face" or how he can overwhelm you with his nonstop energy. He does hate being alone, hates loud sounds and doesn't seem to have the same "logical" way of processing information that his older sister does. He seems to require constant reassurance and direction. He doesn't have a security blanket, but he loves video games (Sonic and Mario) and when he's not playing video games or watching "Max & Ruby" he wants to eat constantly - I think he's using food as his "security blanket". He seems unable to play by himself and is poor at following directions. Depending on his mood, he's either very friendly with other kids, or doesn't want to participate in group play. He can be very stubborn, and although he cries very easily, he doesn't really have meltdowns in public, doesn't do the screaming tantrum, etc. but he's very compassionate, loving, affectionate and just overall a happy kid. I don't treat him any differently and than his neurotypical sister and I never coddle him- I've found that consistent discipline keeps him from becoming defiant and a brat. He's just too high-energy for me and has made managing my own condition very difficult (I have rheumatoid and psoriatic arthritis - sleep poorly and struggle with fatigue, pain and stiffness daily).

I'd love to hear from adult HFA or Asperger's or parents of such children in terms of what to expect, tips on how to handle the challenges. I want to understand more about how he views and processes things. I'm nervous other kids will make fun of him or pick on him for being a little different even if he looks no different than any other kid his age.
I'm physically and emotionally exhausted at times just caring for him. He sometimes wakes up early and he goes nonstop until late at night; I love him more than anything but some days are rougher than others - the nonstop talking and rambling, the neverending questions, the neverending asking for food, or video games having to correct and redirect him constantly, it just takes a toll on me. The constantness of it can drive me nuts. Now with a diagnosis it's easier for me to try to understand him but I would welcome any helpful tips on how to cope and what to expect going forward.

Sorry for rambling, I really needed to vent.