New here son recently diagnosed with ASD

Hi there not quite sure what to write here to be honest but here goes my son is just over 3 and a half will be 4 in February he has recently been diagnosed with asd. Me and my wife had been concerned for a while with some of my sons behaviours mainly communication but had been going back a fourth wondering whether it was just speech delay or autism. We had been going through Isend support and speech and language and recently went to the hospital where within observing my son for 10 minutes the doctor said he was autistic said and I quote "well you must have known" to which I replied no as I wasnt sure the reasons she gave were that he didnt make eye contact or have shared enjoyment both traits which he does with us at home which I said, she then said he is 100% autistic gave us a few leaflets and sent us on our way which was quite upsetting for me and my partner! Since this meeting which was 3 weeks ago now we have heard nothing and are a bit of a loss of how to help him also if I'm honest I feel like I am still in a bit of denial as i have looked into autism alot and feel like my son doesnt have many of the "usual" traits of an autistic child although i do appreciate i am most likely wrong as I have been told he is by a doctor. Sorry to ramble on but just havent really had anywhere I could let this out any advice would be greatly appreciated :)