You write that you’re super nervous for him; calming your boy starts with calming yourself…he will pick up on your anxiety.
What I’ve done in the case of medial exams and surgeries;
watch video’s on youtube kids
make a wee story book or picture template about what’s going to happen (a simple social story) and prepare your child

I remember my brother having that surgery as a teenager. It was very straightforward. I hope your son is home with you after no complications.

Stay strong mumma, he will pick up on your anxieties. Best wishes xx

My son had this done at 14 months, it was super easy and quick, make sure you chat with him about what will happen to prepare him. I am a theatre nurse so that bit was easy for me though. The hospitals are used to dealing with little kids and will make it easy

Your worring is not going to change anything.