Pre-k teacher mentioned “red flags” - don’t know what to be worried about and it’s worrying me

I was pulled aside by my 4.5 year’s old pre k teacher this morning after a family event, and she nervously told me there were some red flags she was worried about with my son. She never outright mentioned autism, but it was like we were speaking in code. She was also extremely apologetic, which threw me off. I contacted my pediatrician to push further and follow up, but was wondering if I could get some feedback while I sit over here and worry.The first was he cries (gets very upset, covers his ears) at a specific letter show they watch in the classroom. This I was not surprised to hear. The first time this happened, the teacher told my mom, who drops him off and picks him up from school). My mom asked him about it in the car, and he told her he was worried that the show ended and both teachers were out talking in the hall and he wanted them to turn it off. Now he cries each time it ends, even if they are still in the classroom. He is also has begun to be particular about this at home, and begs us to turn off the tv at the end of each show so it doesn’t start the next thing on the DVR.The second was that when he first enters the classroom he wrings and flaps his hands until he settles into a toy during free play. This one stunned me. I have never seen him do this at home or when we go out. My mom says he is usually quiet and reserved, and nervous when she drops him off. Not his usually upbeat self. He kind of gets withdrawn. After she picks him up he usually chats the whole way home and seems to have enjoyed the school dayLast she says he does not approach other kids to play, rather lets them come to him, and only then he plays with them. I speak with him after school and he’s able to tell me who and what he’s played with. He doesn’t have a ton of friends, mainly another boy who is also very quiet, who he knows by name. He is very shy, and didn’t speak almost the whole time he was in 3 y/o pre-k in spite of almost never stopping talking at home with his family. I was really surprised when they told me he never talked! He is doing much better this year verbally and is interacting a lot more. I have also seen him play with his younger brother daily, cousin of similar age, and he occasionally talks to stranger kids on the playground and initiates play with them. He’s always very interested in other kids, even if he is not feeling brave enough to approach them. He also has no problem playing with and interacting with adults after a brief warm up period.I am extremely worried and guilty that I have somehow overlooked warning signs and have missed the opportunity for early intervention. He just seemed typical to me. Does this sound like he might be on the spectrum? Anxiety about school? I just want to make sure he remains the happy boy he is and help him improve if he needs it. via /r/Parenting http://ift.tt/2E5qfkO