i don't know

I don't know if the little "fits" that Holden's throwing are normal, everyday, typical toddler "fits". Or are they due to the autistic behaviors? He'll be 2 in 2.5 weeks. So, one should expect that he would start doing toddler things, right? Like tantrums, for instance. But, how do I know if it's normal behavior, or if it's because he's resistent to change or he's over stimulated? Today we went to the park. Before we left the house, I turned off his Baby Einstein video and he cried. Cried in the car for about 30 seconds, and by the time we were out of the driveway, he was fine. We went to the park and I let him swing for about 15-20 minutes at which time he looked and smiled at his sister and another little girl who were swinging next to him. I swore I even heard him say "issy" for sissy. But, I don't know for sure. I take him and let him walk around a little, where he ignored the kids, and walked through the rocks and mulch. After about 5 minutes, I told him we had to go. I picked him up and he started squirming - trying to get down. Then came the crying (as he could see we were walking towards the car), and the screaming. Crying and screaming when I put him in the carseat. And once we were out of the driveway of the park, he was done. I wondered all the way home if this was just a normal toddler meltdown, or if it's part of his autistic behaviors. I DON'T KNOW and it's frustrating as all hell.