My son had this operation 6 1/2 years ago.
His was picked up by the GP at his newborn check, and he had the op when he was 7 months old.
About a week or so before a nurse rang me and explained the whole procedure. He was lovely and said this is like bread and butter to them; they do them all the time and it's a pretty straightforward procedure. But he understood that it's not bread and butter for the parents and it's completely understandable to be worried about your little one. He told me to just take one step at a time - focus on getting to the hospital, then on getting to surgery etc.
On the day we drove at the crack of dawn to our nearest children's hospital. The order of outpatients surgery was based on age so DS should have been first. But there had been an emergency overnight and some equipment now needed to be sterilised, so we were pushed to last. This was the worst part because DS was nil-by-mouth and was starving by the time he went down to theatre. I felt so bad about all the crying, but there was nothing I could do by the end!
I went into the anaesthetic room with him and DH waited outside. I sat him on my knee and they played with a toy to distract him, then held a mask near his mouth until he fell asleep. I cuddled him the whole time - in fact so much I had to be reminded not to get too close in case I breathed it in myself (I did feel a bit woozy when I stood up!)
We had a coffee and then went back up to the ward. The ward staff were great, told us as soon as he was out and in recovery.
He was awake when he was brought back up to the ward. And I did feel guilty he would have come round surrounded by strangers but he'd obviously been well cared for and I reassured myself he wouldn't remember it.
Because he was last the surgeon came with him and explained what they had found.
DS was very very upset when he came back on the ward though. I actually thought he was struggling to breathe but it's just because he'd cried so hard he'd got into a state and couldn't catch his breath back. As soon as he was given painkillers he calmed down and was able to feed and then he was fine. We went home only a few hours after his surgery.
Recovery was quick and easy. He had a check up locally about a year later. And just a few weeks ago I had a chat with him about it - he's 7 now so needs to know he should be extra careful when doing some activities.
Completely understandable that you'd be upset - I'm sure I cried! I knew logically that it was common and straightforward and that DS would be absolutely fine, but it's not so easy to think logically when it's your baby!