My Little Boy is not your NORMAL Child

Hey, This is most likely my hardest post that I have to write at this time. Miles is very different than his older sister. At first, I just thought it was because he was looking up to his sister and she just talked for him. But, things have changed in my little boy. Miles is now twenty-one months old and he is only speaking up to four words, "yeah, mama, no, please." It started to concern me that he was not picking up words like I have seen other little kids his age were. Then...his nights turned bad to worse. He was waking up not just once but every hour at night. Which became harder and harder for me who is pregnant with another baby. I was often crying in the morning when it was time to get up. Then there were nights where he would be screaming for an hour and nothing could calm him. For this, I was able to take a video and show it to a doctor who told me that it was not night terrors as he was responding to my voice through the melt down. Then the meltdowns started during the day as well. At first they were like a normal toddler meltdown then they turned longer. We were having meltdowns for very little things that were lasting hours. With much tears from myself, Miles, and Ginny. So at first we started to put him in his room and he would only let us open his door when he was calm enough. Well, he had a bruise on his forehead after one session of a meltdown. So the next time I watched him during another one and watched as he ran head first into the wall, and door. Then he started to bite himself during the meltdowns. He also started to turn agressive to others during his meltdowns. He would kick, scream, bite, hit, and run at you head first. Not only was he doing it to myself, Stephen, and my mom, but Ginny as well. My sweet, cuddly boy was having some problems. We started to worry about the future. Is there a chance that he could hurt the baby when it comes during a meltdown? We started calling Children's Mercy, KU, Olathe School district, as well as Infant Toddler program. Anyone that can help us...it took us crying on the phone to finally get someone to help us. Miles is now being evaluated on his behaviors to see if something else is going on. Autism has been thrown out in words. Something that I have wondered since I work with autistic children. Is it scary...very much so...but right now it's scary of not knowing. It's taking everything to keep myself a float. I often cry myself to sleep of frustration of not helping him. Stephen and I struggle with a normal marriage, and I struggle to not take my frustration out on him as well as Ginny. Ginny is starting to act out because of feeling left out and it breaks my heart. I have been called a BAD MOTHER by others and even myself. Did I do something...to create this? Did I create my little boy not being able to handle things? If I did how can I make sure I do not do it again? How can I help my little boy? How will I handle this issue going on and having another baby? Is this even fair to Ginny as well as the baby? I worry and stress all the time...no one knows what's going through my mind... AM I A HORRIBLE MOTHER?